const EventEmitter = require('events');
const hull = require('hull.js');
const twgl = require('twgl.js');
const BitmapSkin = require('./BitmapSkin');
const Drawable = require('./Drawable');
const Rectangle = require('./Rectangle');
const PenSkin = require('./PenSkin');
const RenderConstants = require('./RenderConstants');
const ShaderManager = require('./ShaderManager');
const SVGSkin = require('./SVGSkin');
const TextBubbleSkin = require('./TextBubbleSkin');
const EffectTransform = require('./EffectTransform');
const log = require('./util/log');
const __isTouchingDrawablesPoint = twgl.v3.create();
const __candidatesBounds = new Rectangle();
const __fenceBounds = new Rectangle();
const __touchingColor = new Uint8ClampedArray(4);
const __blendColor = new Uint8ClampedArray(4);
// More pixels than this and we give up to the GPU and take the cost of readPixels
// Width * Height * Number of drawables at location
const __cpuTouchingColorPixelCount = 4e4;
/**
* @callback RenderWebGL#idFilterFunc
* @param {int} drawableID The ID to filter.
* @return {bool} True if the ID passes the filter, otherwise false.
*/
/**
* Maximum touch size for a picking check.
* @todo Figure out a reasonable max size. Maybe this should be configurable?
* @type {Array<int>}
* @memberof RenderWebGL
*/
const MAX_TOUCH_SIZE = [3, 3];
/**
* Passed to the uniforms for mask in touching color
*/
const MASK_TOUCHING_COLOR_TOLERANCE = 2;
/**
* Maximum number of pixels in either dimension of "extracted drawable" data
* @type {int}
*/
const MAX_EXTRACTED_DRAWABLE_DIMENSION = 2048;
/**
* Determines if the mask color is "close enough" (only test the 6 top bits for
* each color). These bit masks are what scratch 2 used to use, so we do the same.
* @param {Uint8Array} a A color3b or color4b value.
* @param {Uint8Array} b A color3b or color4b value.
* @returns {boolean} If the colors match within the parameters.
*/
const maskMatches = (a, b) => (
// has some non-alpha component to test against
a[3] > 0 &&
(a[0] & 0b11111100) === (b[0] & 0b11111100) &&
(a[1] & 0b11111100) === (b[1] & 0b11111100) &&
(a[2] & 0b11111100) === (b[2] & 0b11111100)
);
/**
* Determines if the given color is "close enough" (only test the 5 top bits for
* red and green, 4 bits for blue). These bit masks are what scratch 2 used to use,
* so we do the same.
* @param {Uint8Array} a A color3b or color4b value.
* @param {Uint8Array} b A color3b or color4b value / or a larger array when used with offsets
* @param {number} offset An offset into the `b` array, which lets you use a larger array to test
* multiple values at the same time.
* @returns {boolean} If the colors match within the parameters.
*/
const colorMatches = (a, b, offset) => (
(a[0] & 0b11111000) === (b[offset + 0] & 0b11111000) &&
(a[1] & 0b11111000) === (b[offset + 1] & 0b11111000) &&
(a[2] & 0b11110000) === (b[offset + 2] & 0b11110000)
);
/**
* Sprite Fencing - The number of pixels a sprite is required to leave remaining
* onscreen around the edge of the staging area.
* @type {number}
*/
const FENCE_WIDTH = 15;
class RenderWebGL extends EventEmitter {
/**
* Check if this environment appears to support this renderer before attempting to create an instance.
* Catching an exception from the constructor is also a valid way to test for (lack of) support.
* @param {canvas} [optCanvas] - An optional canvas to use for the test. Otherwise a temporary canvas will be used.
* @returns {boolean} - True if this environment appears to support this renderer, false otherwise.
*/
static isSupported (optCanvas) {
try {
// Create the context the same way that the constructor will: attributes may make the difference.
return !!RenderWebGL._getContext(optCanvas || document.createElement('canvas'));
} catch (e) {
return false;
}
}
/**
* Ask TWGL to create a rendering context with the attributes used by this renderer.
* @param {canvas} canvas - attach the context to this canvas.
* @returns {WebGLRenderingContext} - a TWGL rendering context (backed by either WebGL 1.0 or 2.0).
* @private
*/
static _getContext (canvas) {
const contextAttribs = {alpha: false, stencil: true, antialias: false};
// getWebGLContext = try WebGL 1.0 only
// getContext = try WebGL 2.0 and if that doesn't work, try WebGL 1.0
// getWebGLContext || getContext = try WebGL 1.0 and if that doesn't work, try WebGL 2.0
return twgl.getWebGLContext(canvas, contextAttribs) ||
twgl.getContext(canvas, contextAttribs);
}
/**
* Create a renderer for drawing Scratch sprites to a canvas using WebGL.
* Coordinates will default to Scratch 2.0 values if unspecified.
* The stage's "native" size will be calculated from the these coordinates.
* For example, the defaults result in a native size of 480x360.
* Queries such as "touching color?" will always execute at the native size.
* @see RenderWebGL#setStageSize
* @see RenderWebGL#resize
* @param {canvas} canvas The canvas to draw onto.
* @param {int} [xLeft=-240] The x-coordinate of the left edge.
* @param {int} [xRight=240] The x-coordinate of the right edge.
* @param {int} [yBottom=-180] The y-coordinate of the bottom edge.
* @param {int} [yTop=180] The y-coordinate of the top edge.
* @constructor
* @listens RenderWebGL#event:NativeSizeChanged
*/
constructor (canvas, xLeft, xRight, yBottom, yTop) {
super();
/** @type {WebGLRenderingContext} */
const gl = this._gl = RenderWebGL._getContext(canvas);
if (!gl) {
throw new Error('Could not get WebGL context: this browser or environment may not support WebGL.');
}
/** @type {RenderWebGL.UseGpuModes} */
this._useGpuMode = RenderWebGL.UseGpuModes.Automatic;
/** @type {Drawable[]} */
this._allDrawables = [];
/** @type {Skin[]} */
this._allSkins = [];
/** @type {Array<int>} */
this._drawList = [];
// A list of layer group names in the order they should appear
// from furthest back to furthest in front.
/** @type {Array<String>} */
this._groupOrdering = [];
/**
* @typedef LayerGroup
* @property {int} groupIndex The relative position of this layer group in the group ordering
* @property {int} drawListOffset The absolute position of this layer group in the draw list
* This number gets updated as drawables get added to or deleted from the draw list.
*/
// Map of group name to layer group
/** @type {Object.<string, LayerGroup>} */
this._layerGroups = {};
/** @type {int} */
this._nextDrawableId = RenderConstants.ID_NONE + 1;
/** @type {int} */
this._nextSkinId = RenderConstants.ID_NONE + 1;
/** @type {module:twgl/m4.Mat4} */
this._projection = twgl.m4.identity();
/** @type {ShaderManager} */
this._shaderManager = new ShaderManager(gl);
/** @type {HTMLCanvasElement} */
this._tempCanvas = document.createElement('canvas');
/** @type {any} */
this._regionId = null;
/** @type {function} */
this._exitRegion = null;
/** @type {object} */
this._backgroundDrawRegionId = {
enter: () => this._enterDrawBackground(),
exit: () => this._exitDrawBackground()
};
/** @type {Array.<snapshotCallback>} */
this._snapshotCallbacks = [];
/** @type {Array<number>} */
// Don't set this directly-- use setBackgroundColor so it stays in sync with _backgroundColor3b
this._backgroundColor4f = [0, 0, 0, 1];
/** @type {Uint8ClampedArray} */
// Don't set this directly-- use setBackgroundColor so it stays in sync with _backgroundColor4f
this._backgroundColor3b = new Uint8ClampedArray(3);
this._createGeometry();
this.on(RenderConstants.Events.NativeSizeChanged, this.onNativeSizeChanged);
this.setBackgroundColor(1, 1, 1);
this.setStageSize(xLeft || -240, xRight || 240, yBottom || -180, yTop || 180);
this.resize(this._nativeSize[0], this._nativeSize[1]);
gl.disable(gl.DEPTH_TEST);
/** @todo disable when no partial transparency? */
gl.enable(gl.BLEND);
gl.blendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA);
}
/**
* @returns {WebGLRenderingContext} the WebGL rendering context associated with this renderer.
*/
get gl () {
return this._gl;
}
/**
* @returns {HTMLCanvasElement} the canvas of the WebGL rendering context associated with this renderer.
*/
get canvas () {
return this._gl && this._gl.canvas;
}
/**
* Set the physical size of the stage in device-independent pixels.
* This will be multiplied by the device's pixel ratio on high-DPI displays.
* @param {int} pixelsWide The desired width in device-independent pixels.
* @param {int} pixelsTall The desired height in device-independent pixels.
*/
resize (pixelsWide, pixelsTall) {
const {canvas} = this._gl;
const pixelRatio = window.devicePixelRatio || 1;
const newWidth = pixelsWide * pixelRatio;
const newHeight = pixelsTall * pixelRatio;
// Certain operations, such as moving the color picker, call `resize` once per frame, even though the canvas
// size doesn't change. To avoid unnecessary canvas updates, check that we *really* need to resize the canvas.
if (canvas.width !== newWidth || canvas.height !== newHeight) {
canvas.width = newWidth;
canvas.height = newHeight;
// Resizing the canvas causes it to be cleared, so redraw it.
this.draw();
}
}
/**
* Set the background color for the stage. The stage will be cleared with this
* color each frame.
* @param {number} red The red component for the background.
* @param {number} green The green component for the background.
* @param {number} blue The blue component for the background.
*/
setBackgroundColor (red, green, blue) {
this._backgroundColor4f[0] = red;
this._backgroundColor4f[1] = green;
this._backgroundColor4f[2] = blue;
this._backgroundColor3b[0] = red * 255;
this._backgroundColor3b[1] = green * 255;
this._backgroundColor3b[2] = blue * 255;
}
/**
* Tell the renderer to draw various debug information to the provided canvas
* during certain operations.
* @param {canvas} canvas The canvas to use for debug output.
*/
setDebugCanvas (canvas) {
this._debugCanvas = canvas;
}
/**
* Control the use of the GPU or CPU paths in `isTouchingColor`.
* @param {RenderWebGL.UseGpuModes} useGpuMode - automatically decide, force CPU, or force GPU.
*/
setUseGpuMode (useGpuMode) {
this._useGpuMode = useGpuMode;
}
/**
* Set logical size of the stage in Scratch units.
* @param {int} xLeft The left edge's x-coordinate. Scratch 2 uses -240.
* @param {int} xRight The right edge's x-coordinate. Scratch 2 uses 240.
* @param {int} yBottom The bottom edge's y-coordinate. Scratch 2 uses -180.
* @param {int} yTop The top edge's y-coordinate. Scratch 2 uses 180.
*/
setStageSize (xLeft, xRight, yBottom, yTop) {
this._xLeft = xLeft;
this._xRight = xRight;
this._yBottom = yBottom;
this._yTop = yTop;
// swap yBottom & yTop to fit Scratch convention of +y=up
this._projection = twgl.m4.ortho(xLeft, xRight, yBottom, yTop, -1, 1);
this._setNativeSize(Math.abs(xRight - xLeft), Math.abs(yBottom - yTop));
}
/**
* @return {Array<int>} the "native" size of the stage, which is used for pen, query renders, etc.
*/
getNativeSize () {
return [this._nativeSize[0], this._nativeSize[1]];
}
/**
* Set the "native" size of the stage, which is used for pen, query renders, etc.
* @param {int} width - the new width to set.
* @param {int} height - the new height to set.
* @private
* @fires RenderWebGL#event:NativeSizeChanged
*/
_setNativeSize (width, height) {
this._nativeSize = [width, height];
this.emit(RenderConstants.Events.NativeSizeChanged, {newSize: this._nativeSize});
}
/**
* Create a new bitmap skin from a snapshot of the provided bitmap data.
* @param {ImageData|HTMLImageElement|HTMLCanvasElement|HTMLVideoElement} bitmapData - new contents for this skin.
* @param {!int} [costumeResolution=1] - The resolution to use for this bitmap.
* @param {?Array<number>} [rotationCenter] Optional: rotation center of the skin. If not supplied, the center of
* the skin will be used.
* @returns {!int} the ID for the new skin.
*/
createBitmapSkin (bitmapData, costumeResolution, rotationCenter) {
const skinId = this._nextSkinId++;
const newSkin = new BitmapSkin(skinId, this);
newSkin.setBitmap(bitmapData, costumeResolution, rotationCenter);
this._allSkins[skinId] = newSkin;
return skinId;
}
/**
* Create a new SVG skin.
* @param {!string} svgData - new SVG to use.
* @param {?Array<number>} rotationCenter Optional: rotation center of the skin. If not supplied, the center of the
* skin will be used
* @returns {!int} the ID for the new skin.
*/
createSVGSkin (svgData, rotationCenter) {
const skinId = this._nextSkinId++;
const newSkin = new SVGSkin(skinId, this);
newSkin.setSVG(svgData, rotationCenter);
this._allSkins[skinId] = newSkin;
return skinId;
}
/**
* Create a new PenSkin - a skin which implements a Scratch pen layer.
* @returns {!int} the ID for the new skin.
*/
createPenSkin () {
const skinId = this._nextSkinId++;
const newSkin = new PenSkin(skinId, this);
this._allSkins[skinId] = newSkin;
return skinId;
}
/**
* Create a new SVG skin using the text bubble svg creator. The rotation center
* is always placed at the top left.
* @param {!string} type - either "say" or "think".
* @param {!string} text - the text for the bubble.
* @param {!boolean} pointsLeft - which side the bubble is pointing.
* @returns {!int} the ID for the new skin.
*/
createTextSkin (type, text, pointsLeft) {
const skinId = this._nextSkinId++;
const newSkin = new TextBubbleSkin(skinId, this);
newSkin.setTextBubble(type, text, pointsLeft);
this._allSkins[skinId] = newSkin;
return skinId;
}
/**
* Update an existing SVG skin, or create an SVG skin if the previous skin was not SVG.
* @param {!int} skinId the ID for the skin to change.
* @param {!string} svgData - new SVG to use.
* @param {?Array<number>} rotationCenter Optional: rotation center of the skin. If not supplied, the center of the
* skin will be used
*/
updateSVGSkin (skinId, svgData, rotationCenter) {
if (this._allSkins[skinId] instanceof SVGSkin) {
this._allSkins[skinId].setSVG(svgData, rotationCenter);
return;
}
const newSkin = new SVGSkin(skinId, this);
newSkin.setSVG(svgData, rotationCenter);
this._reskin(skinId, newSkin);
}
/**
* Update an existing bitmap skin, or create a bitmap skin if the previous skin was not bitmap.
* @param {!int} skinId the ID for the skin to change.
* @param {!ImageData|HTMLImageElement|HTMLCanvasElement|HTMLVideoElement} imgData - new contents for this skin.
* @param {!number} bitmapResolution - the resolution scale for a bitmap costume.
* @param {?Array<number>} rotationCenter Optional: rotation center of the skin. If not supplied, the center of the
* skin will be used
*/
updateBitmapSkin (skinId, imgData, bitmapResolution, rotationCenter) {
if (this._allSkins[skinId] instanceof BitmapSkin) {
this._allSkins[skinId].setBitmap(imgData, bitmapResolution, rotationCenter);
return;
}
const newSkin = new BitmapSkin(skinId, this);
newSkin.setBitmap(imgData, bitmapResolution, rotationCenter);
this._reskin(skinId, newSkin);
}
_reskin (skinId, newSkin) {
const oldSkin = this._allSkins[skinId];
this._allSkins[skinId] = newSkin;
// Tell drawables to update
for (const drawable of this._allDrawables) {
if (drawable && drawable.skin === oldSkin) {
drawable.skin = newSkin;
}
}
oldSkin.dispose();
}
/**
* Update a skin using the text bubble svg creator.
* @param {!int} skinId the ID for the skin to change.
* @param {!string} type - either "say" or "think".
* @param {!string} text - the text for the bubble.
* @param {!boolean} pointsLeft - which side the bubble is pointing.
*/
updateTextSkin (skinId, type, text, pointsLeft) {
if (this._allSkins[skinId] instanceof TextBubbleSkin) {
this._allSkins[skinId].setTextBubble(type, text, pointsLeft);
return;
}
const newSkin = new TextBubbleSkin(skinId, this);
newSkin.setTextBubble(type, text, pointsLeft);
this._reskin(skinId, newSkin);
}
/**
* Destroy an existing skin. Do not use the skin or its ID after calling this.
* @param {!int} skinId - The ID of the skin to destroy.
*/
destroySkin (skinId) {
const oldSkin = this._allSkins[skinId];
oldSkin.dispose();
delete this._allSkins[skinId];
}
/**
* Create a new Drawable and add it to the scene.
* @param {string} group Layer group to add the drawable to
* @returns {int} The ID of the new Drawable.
*/
createDrawable (group) {
if (!group || !Object.prototype.hasOwnProperty.call(this._layerGroups, group)) {
log.warn('Cannot create a drawable without a known layer group');
return;
}
const drawableID = this._nextDrawableId++;
const drawable = new Drawable(drawableID);
this._allDrawables[drawableID] = drawable;
this._addToDrawList(drawableID, group);
drawable.skin = null;
return drawableID;
}
/**
* Set the layer group ordering for the renderer.
* @param {Array<string>} groupOrdering The ordered array of layer group
* names
*/
setLayerGroupOrdering (groupOrdering) {
this._groupOrdering = groupOrdering;
for (let i = 0; i < this._groupOrdering.length; i++) {
this._layerGroups[this._groupOrdering[i]] = {
groupIndex: i,
drawListOffset: 0
};
}
}
_addToDrawList (drawableID, group) {
const currentLayerGroup = this._layerGroups[group];
const currentGroupOrderingIndex = currentLayerGroup.groupIndex;
const drawListOffset = this._endIndexForKnownLayerGroup(currentLayerGroup);
this._drawList.splice(drawListOffset, 0, drawableID);
this._updateOffsets('add', currentGroupOrderingIndex);
}
_updateOffsets (updateType, currentGroupOrderingIndex) {
for (let i = currentGroupOrderingIndex + 1; i < this._groupOrdering.length; i++) {
const laterGroupName = this._groupOrdering[i];
if (updateType === 'add') {
this._layerGroups[laterGroupName].drawListOffset++;
} else if (updateType === 'delete'){
this._layerGroups[laterGroupName].drawListOffset--;
}
}
}
get _visibleDrawList () {
return this._drawList.filter(id => this._allDrawables[id]._visible);
}
// Given a layer group, return the index where it ends (non-inclusive),
// e.g. the returned index does not have a drawable from this layer group in it)
_endIndexForKnownLayerGroup (layerGroup) {
const groupIndex = layerGroup.groupIndex;
if (groupIndex === this._groupOrdering.length - 1) {
return this._drawList.length;
}
return this._layerGroups[this._groupOrdering[groupIndex + 1]].drawListOffset;
}
/**
* Destroy a Drawable, removing it from the scene.
* @param {int} drawableID The ID of the Drawable to remove.
* @param {string} group Group name that the drawable belongs to
*/
destroyDrawable (drawableID, group) {
if (!group || !Object.prototype.hasOwnProperty.call(this._layerGroups, group)) {
log.warn('Cannot destroy drawable without known layer group.');
return;
}
const drawable = this._allDrawables[drawableID];
drawable.dispose();
delete this._allDrawables[drawableID];
const currentLayerGroup = this._layerGroups[group];
const endIndex = this._endIndexForKnownLayerGroup(currentLayerGroup);
let index = currentLayerGroup.drawListOffset;
while (index < endIndex) {
if (this._drawList[index] === drawableID) {
break;
}
index++;
}
if (index < endIndex) {
this._drawList.splice(index, 1);
this._updateOffsets('delete', currentLayerGroup.groupIndex);
} else {
log.warn('Could not destroy drawable that could not be found in layer group.');
return;
}
}
/**
* Returns the position of the given drawableID in the draw list. This is
* the absolute position irrespective of layer group.
* @param {number} drawableID The drawable ID to find.
* @return {number} The postion of the given drawable ID.
*/
getDrawableOrder (drawableID) {
return this._drawList.indexOf(drawableID);
}
/**
* Set a drawable's order in the drawable list (effectively, z/layer).
* Can be used to move drawables to absolute positions in the list,
* or relative to their current positions.
* "go back N layers": setDrawableOrder(id, -N, true, 1); (assuming stage at 0).
* "go to back": setDrawableOrder(id, 1); (assuming stage at 0).
* "go to front": setDrawableOrder(id, Infinity);
* @param {int} drawableID ID of Drawable to reorder.
* @param {number} order New absolute order or relative order adjusment.
* @param {string=} group Name of layer group drawable belongs to.
* Reordering will not take place if drawable cannot be found within the bounds
* of the layer group.
* @param {boolean=} optIsRelative If set, `order` refers to a relative change.
* @param {number=} optMin If set, order constrained to be at least `optMin`.
* @return {?number} New order if changed, or null.
*/
setDrawableOrder (drawableID, order, group, optIsRelative, optMin) {
if (!group || !Object.prototype.hasOwnProperty.call(this._layerGroups, group)) {
log.warn('Cannot set the order of a drawable without a known layer group.');
return;
}
const currentLayerGroup = this._layerGroups[group];
const startIndex = currentLayerGroup.drawListOffset;
const endIndex = this._endIndexForKnownLayerGroup(currentLayerGroup);
let oldIndex = startIndex;
while (oldIndex < endIndex) {
if (this._drawList[oldIndex] === drawableID) {
break;
}
oldIndex++;
}
if (oldIndex < endIndex) {
// Remove drawable from the list.
if (order === 0) {
return oldIndex;
}
const _ = this._drawList.splice(oldIndex, 1)[0];
// Determine new index.
let newIndex = order;
if (optIsRelative) {
newIndex += oldIndex;
}
const possibleMin = (optMin || 0) + startIndex;
const min = (possibleMin >= startIndex && possibleMin < endIndex) ? possibleMin : startIndex;
newIndex = Math.max(newIndex, min);
newIndex = Math.min(newIndex, endIndex);
// Insert at new index.
this._drawList.splice(newIndex, 0, drawableID);
return newIndex;
}
return null;
}
/**
* Draw all current drawables and present the frame on the canvas.
*/
draw () {
this._doExitDrawRegion();
const gl = this._gl;
twgl.bindFramebufferInfo(gl, null);
gl.viewport(0, 0, gl.canvas.width, gl.canvas.height);
gl.clearColor(...this._backgroundColor4f);
gl.clear(gl.COLOR_BUFFER_BIT);
this._drawThese(this._drawList, ShaderManager.DRAW_MODE.default, this._projection, {
framebufferWidth: gl.canvas.width,
framebufferHeight: gl.canvas.height
});
if (this._snapshotCallbacks.length > 0) {
const snapshot = gl.canvas.toDataURL();
this._snapshotCallbacks.forEach(cb => cb(snapshot));
this._snapshotCallbacks = [];
}
}
/**
* Get the precise bounds for a Drawable.
* @param {int} drawableID ID of Drawable to get bounds for.
* @return {object} Bounds for a tight box around the Drawable.
*/
getBounds (drawableID) {
const drawable = this._allDrawables[drawableID];
// Tell the Drawable about its updated convex hull, if necessary.
if (drawable.needsConvexHullPoints()) {
const points = this._getConvexHullPointsForDrawable(drawableID);
drawable.setConvexHullPoints(points);
}
const bounds = drawable.getFastBounds();
// In debug mode, draw the bounds.
if (this._debugCanvas) {
const gl = this._gl;
this._debugCanvas.width = gl.canvas.width;
this._debugCanvas.height = gl.canvas.height;
const context = this._debugCanvas.getContext('2d');
context.drawImage(gl.canvas, 0, 0);
context.strokeStyle = '#FF0000';
const pr = window.devicePixelRatio;
context.strokeRect(
pr * (bounds.left + (this._nativeSize[0] / 2)),
pr * (-bounds.top + (this._nativeSize[1] / 2)),
pr * (bounds.right - bounds.left),
pr * (-bounds.bottom + bounds.top)
);
}
return bounds;
}
/**
* Get the precise bounds for a Drawable around the top slice.
* Used for positioning speech bubbles more closely to the sprite.
* @param {int} drawableID ID of Drawable to get bubble bounds for.
* @return {object} Bounds for a tight box around the Drawable top slice.
*/
getBoundsForBubble (drawableID) {
const drawable = this._allDrawables[drawableID];
// Tell the Drawable about its updated convex hull, if necessary.
if (drawable.needsConvexHullPoints()) {
const points = this._getConvexHullPointsForDrawable(drawableID);
drawable.setConvexHullPoints(points);
}
const bounds = drawable.getBoundsForBubble();
// In debug mode, draw the bounds.
if (this._debugCanvas) {
const gl = this._gl;
this._debugCanvas.width = gl.canvas.width;
this._debugCanvas.height = gl.canvas.height;
const context = this._debugCanvas.getContext('2d');
context.drawImage(gl.canvas, 0, 0);
context.strokeStyle = '#FF0000';
const pr = window.devicePixelRatio;
context.strokeRect(
pr * (bounds.left + (this._nativeSize[0] / 2)),
pr * (-bounds.top + (this._nativeSize[1] / 2)),
pr * (bounds.right - bounds.left),
pr * (-bounds.bottom + bounds.top)
);
}
return bounds;
}
/**
* Get the current skin (costume) size of a Drawable.
* @param {int} drawableID The ID of the Drawable to measure.
* @return {Array<number>} Skin size, width and height.
*/
getCurrentSkinSize (drawableID) {
const drawable = this._allDrawables[drawableID];
return this.getSkinSize(drawable.skin.id);
}
/**
* Get the size of a skin by ID.
* @param {int} skinID The ID of the Skin to measure.
* @return {Array<number>} Skin size, width and height.
*/
getSkinSize (skinID) {
const skin = this._allSkins[skinID];
return skin.size;
}
/**
* Get the rotation center of a skin by ID.
* @param {int} skinID The ID of the Skin
* @return {Array<number>} The rotationCenterX and rotationCenterY
*/
getSkinRotationCenter (skinID) {
const skin = this._allSkins[skinID];
return skin.calculateRotationCenter();
}
/**
* Check if a particular Drawable is touching a particular color.
* Unlike touching drawable, if the "tester" is invisble, we will still test.
* @param {int} drawableID The ID of the Drawable to check.
* @param {Array<int>} color3b Test if the Drawable is touching this color.
* @param {Array<int>} [mask3b] Optionally mask the check to this part of Drawable.
* @returns {boolean} True iff the Drawable is touching the color.
*/
isTouchingColor (drawableID, color3b, mask3b) {
const candidates = this._candidatesTouching(drawableID, this._visibleDrawList);
let bounds;
if (colorMatches(color3b, this._backgroundColor3b, 0)) {
// If the color we're checking for is the background color, don't confine the check to
// candidate drawables' bounds--since the background spans the entire stage, we must check
// everything that lies inside the drawable.
bounds = this._touchingBounds(drawableID);
// e.g. empty costume, or off the stage
if (bounds === null) return false;
} else if (candidates.length === 0) {
// If not checking for the background color, we can return early if there are no candidate drawables.
return false;
} else {
bounds = this._candidatesBounds(candidates);
}
const maxPixelsForCPU = this._getMaxPixelsForCPU();
const debugCanvasContext = this._debugCanvas && this._debugCanvas.getContext('2d');
if (debugCanvasContext) {
this._debugCanvas.width = bounds.width;
this._debugCanvas.height = bounds.height;
}
// if there are just too many pixels to CPU render efficiently, we need to let readPixels happen
if (bounds.width * bounds.height * (candidates.length + 1) >= maxPixelsForCPU) {
this._isTouchingColorGpuStart(drawableID, candidates.map(({id}) => id).reverse(), bounds, color3b, mask3b);
}
const drawable = this._allDrawables[drawableID];
const point = __isTouchingDrawablesPoint;
const color = __touchingColor;
const hasMask = Boolean(mask3b);
drawable.updateCPURenderAttributes();
// Masked drawable ignores ghost effect
const effectMask = ~ShaderManager.EFFECT_INFO.ghost.mask;
// Scratch Space - +y is top
for (let y = bounds.bottom; y <= bounds.top; y++) {
if (bounds.width * (y - bounds.bottom) * (candidates.length + 1) >= maxPixelsForCPU) {
return this._isTouchingColorGpuFin(bounds, color3b, y - bounds.bottom);
}
for (let x = bounds.left; x <= bounds.right; x++) {
point[1] = y;
point[0] = x;
// if we use a mask, check our sample color...
if (hasMask ?
maskMatches(Drawable.sampleColor4b(point, drawable, color, effectMask), mask3b) :
drawable.isTouching(point)) {
RenderWebGL.sampleColor3b(point, candidates, color);
if (debugCanvasContext) {
debugCanvasContext.fillStyle = `rgb(${color[0]},${color[1]},${color[2]})`;
debugCanvasContext.fillRect(x - bounds.left, bounds.bottom - y, 1, 1);
}
// ...and the target color is drawn at this pixel
if (colorMatches(color, color3b, 0)) {
return true;
}
}
}
}
return false;
}
_getMaxPixelsForCPU () {
switch (this._useGpuMode) {
case RenderWebGL.UseGpuModes.ForceCPU:
return Infinity;
case RenderWebGL.UseGpuModes.ForceGPU:
return 0;
case RenderWebGL.UseGpuModes.Automatic:
default:
return __cpuTouchingColorPixelCount;
}
}
_enterDrawBackground () {
const gl = this.gl;
const currentShader = this._shaderManager.getShader(ShaderManager.DRAW_MODE.background, 0);
gl.disable(gl.BLEND);
gl.useProgram(currentShader.program);
twgl.setBuffersAndAttributes(gl, currentShader, this._bufferInfo);
}
_exitDrawBackground () {
const gl = this.gl;
gl.enable(gl.BLEND);
}
_isTouchingColorGpuStart (drawableID, candidateIDs, bounds, color3b, mask3b) {
this._doExitDrawRegion();
const gl = this._gl;
twgl.bindFramebufferInfo(gl, this._queryBufferInfo);
// Limit size of viewport to the bounds around the target Drawable,
// and create the projection matrix for the draw.
gl.viewport(0, 0, bounds.width, bounds.height);
const projection = twgl.m4.ortho(bounds.left, bounds.right, bounds.top, bounds.bottom, -1, 1);
// Clear the query buffer to fully transparent. This will be the color of pixels that fail the stencil test.
gl.clearColor(0, 0, 0, 0);
gl.clear(gl.COLOR_BUFFER_BIT | gl.STENCIL_BUFFER_BIT);
let extraUniforms;
if (mask3b) {
extraUniforms = {
u_colorMask: [mask3b[0] / 255, mask3b[1] / 255, mask3b[2] / 255],
u_colorMaskTolerance: MASK_TOUCHING_COLOR_TOLERANCE / 255
};
}
try {
// Using the stencil buffer, mask out the drawing to either the drawable's alpha channel
// or pixels of the drawable which match the mask color, depending on whether a mask color is given.
// Masked-out pixels will not be checked.
gl.enable(gl.STENCIL_TEST);
gl.stencilFunc(gl.ALWAYS, 1, 1);
gl.stencilOp(gl.KEEP, gl.KEEP, gl.REPLACE);
gl.colorMask(false, false, false, false);
this._drawThese(
[drawableID],
mask3b ?
ShaderManager.DRAW_MODE.colorMask :
ShaderManager.DRAW_MODE.silhouette,
projection,
{
extraUniforms,
ignoreVisibility: true, // Touching color ignores sprite visibility,
effectMask: ~ShaderManager.EFFECT_INFO.ghost.mask
});
gl.stencilFunc(gl.EQUAL, 1, 1);
gl.stencilOp(gl.KEEP, gl.KEEP, gl.KEEP);
gl.colorMask(true, true, true, true);
// Draw the background as a quad. Drawing a background with gl.clear will not mask to the stenciled area.
this.enterDrawRegion(this._backgroundDrawRegionId);
const uniforms = {
u_backgroundColor: this._backgroundColor4f
};
const currentShader = this._shaderManager.getShader(ShaderManager.DRAW_MODE.background, 0);
twgl.setUniforms(currentShader, uniforms);
twgl.drawBufferInfo(gl, this._bufferInfo, gl.TRIANGLES);
// Draw the candidate drawables on top of the background.
this._drawThese(candidateIDs, ShaderManager.DRAW_MODE.default, projection,
{idFilterFunc: testID => testID !== drawableID}
);
} finally {
gl.colorMask(true, true, true, true);
gl.disable(gl.STENCIL_TEST);
this._doExitDrawRegion();
}
}
_isTouchingColorGpuFin (bounds, color3b, stop) {
const gl = this._gl;
const pixels = new Uint8Array(Math.floor(bounds.width * (bounds.height - stop) * 4));
gl.readPixels(0, 0, bounds.width, (bounds.height - stop), gl.RGBA, gl.UNSIGNED_BYTE, pixels);
if (this._debugCanvas) {
this._debugCanvas.width = bounds.width;
this._debugCanvas.height = bounds.height;
const context = this._debugCanvas.getContext('2d');
const imageData = context.getImageData(0, 0, bounds.width, bounds.height - stop);
imageData.data.set(pixels);
context.putImageData(imageData, 0, 0);
}
for (let pixelBase = 0; pixelBase < pixels.length; pixelBase += 4) {
// Transparent pixels are masked (either by the drawable's alpha channel or color mask).
if (pixels[pixelBase + 3] !== 0 && colorMatches(color3b, pixels, pixelBase)) {
return true;
}
}
return false;
}
/**
* Check if a particular Drawable is touching any in a set of Drawables.
* @param {int} drawableID The ID of the Drawable to check.
* @param {?Array<int>} candidateIDs The Drawable IDs to check, otherwise all visible drawables in the renderer
* @returns {boolean} True if the Drawable is touching one of candidateIDs.
*/
isTouchingDrawables (drawableID, candidateIDs = this._drawList) {
const candidates = this._candidatesTouching(drawableID,
// even if passed an invisible drawable, we will NEVER touch it!
candidateIDs.filter(id => this._allDrawables[id]._visible));
// if we are invisble we don't touch anything.
if (candidates.length === 0 || !this._allDrawables[drawableID]._visible) {
return false;
}
// Get the union of all the candidates intersections.
const bounds = this._candidatesBounds(candidates);
const drawable = this._allDrawables[drawableID];
const point = __isTouchingDrawablesPoint;
drawable.updateCPURenderAttributes();
// This is an EXTREMELY brute force collision detector, but it is
// still faster than asking the GPU to give us the pixels.
for (let x = bounds.left; x <= bounds.right; x++) {
// Scratch Space - +y is top
point[0] = x;
for (let y = bounds.bottom; y <= bounds.top; y++) {
point[1] = y;
if (drawable.isTouching(point)) {
for (let index = 0; index < candidates.length; index++) {
if (candidates[index].drawable.isTouching(point)) {
return true;
}
}
}
}
}
return false;
}
/**
* Convert a client based x/y position on the canvas to a Scratch 3 world space
* Rectangle. This creates recangles with a radius to cover selecting multiple
* scratch pixels with touch / small render areas.
*
* @param {int} centerX The client x coordinate of the picking location.
* @param {int} centerY The client y coordinate of the picking location.
* @param {int} [width] The client width of the touch event (optional).
* @param {int} [height] The client width of the touch event (optional).
* @returns {Rectangle} Scratch world space rectangle, iterate bottom <= top,
* left <= right.
*/
clientSpaceToScratchBounds (centerX, centerY, width = 1, height = 1) {
const gl = this._gl;
const clientToScratchX = this._nativeSize[0] / gl.canvas.clientWidth;
const clientToScratchY = this._nativeSize[1] / gl.canvas.clientHeight;
width *= clientToScratchX;
height *= clientToScratchY;
width = Math.max(1, Math.min(Math.round(width), MAX_TOUCH_SIZE[0]));
height = Math.max(1, Math.min(Math.round(height), MAX_TOUCH_SIZE[1]));
const x = (centerX * clientToScratchX) - ((width - 1) / 2);
// + because scratch y is inverted
const y = (centerY * clientToScratchY) + ((height - 1) / 2);
const xOfs = (width % 2) ? 0 : -0.5;
// y is offset +0.5
const yOfs = (height % 2) ? 0 : -0.5;
const bounds = new Rectangle();
bounds.initFromBounds(Math.floor(this._xLeft + x + xOfs), Math.floor(this._xLeft + x + xOfs + width - 1),
Math.ceil(this._yTop - y + yOfs), Math.ceil(this._yTop - y + yOfs + height - 1));
return bounds;
}
/**
* Determine if the drawable is touching a client based x/y. Helper method for sensing
* touching mouse-pointer. Ignores visibility.
*
* @param {int} drawableID The ID of the drawable to check.
* @param {int} centerX The client x coordinate of the picking location.
* @param {int} centerY The client y coordinate of the picking location.
* @param {int} [touchWidth] The client width of the touch event (optional).
* @param {int} [touchHeight] The client height of the touch event (optional).
* @returns {boolean} If the drawable has any pixels that would draw in the touch area
*/
drawableTouching (drawableID, centerX, centerY, touchWidth, touchHeight) {
const drawable = this._allDrawables[drawableID];
if (!drawable) {
return false;
}
const bounds = this.clientSpaceToScratchBounds(centerX, centerY, touchWidth, touchHeight);
const worldPos = twgl.v3.create();
drawable.updateCPURenderAttributes();
for (worldPos[1] = bounds.bottom; worldPos[1] <= bounds.top; worldPos[1]++) {
for (worldPos[0] = bounds.left; worldPos[0] <= bounds.right; worldPos[0]++) {
if (drawable.isTouching(worldPos)) {
return true;
}
}
}
return false;
}
/**
* Detect which sprite, if any, is at the given location.
* This function will pick all drawables that are visible, unless specific
* candidate drawable IDs are provided. Used for determining what is clicked
* or dragged. Will not select hidden / ghosted sprites.
*
* @param {int} centerX The client x coordinate of the picking location.
* @param {int} centerY The client y coordinate of the picking location.
* @param {int} [touchWidth] The client width of the touch event (optional).
* @param {int} [touchHeight] The client height of the touch event (optional).
* @param {Array<int>} [candidateIDs] The Drawable IDs to pick from, otherwise all visible drawables.
* @returns {int} The ID of the topmost Drawable under the picking location, or
* RenderConstants.ID_NONE if there is no Drawable at that location.
*/
pick (centerX, centerY, touchWidth, touchHeight, candidateIDs) {
const bounds = this.clientSpaceToScratchBounds(centerX, centerY, touchWidth, touchHeight);
if (bounds.left === -Infinity || bounds.bottom === -Infinity) {
return false;
}
candidateIDs = (candidateIDs || this._drawList).filter(id => {
const drawable = this._allDrawables[id];
// default pick list ignores visible and ghosted sprites.
if (drawable.getVisible() && drawable.getUniforms().u_ghost !== 0) {
const drawableBounds = drawable.getFastBounds();
const inRange = bounds.intersects(drawableBounds);
if (!inRange) return false;
drawable.updateCPURenderAttributes();
return true;
}
return false;
});
if (candidateIDs.length === 0) {
return false;
}
const hits = [];
const worldPos = twgl.v3.create(0, 0, 0);
// Iterate over the scratch pixels and check if any candidate can be
// touched at that point.
for (worldPos[1] = bounds.bottom; worldPos[1] <= bounds.top; worldPos[1]++) {
for (worldPos[0] = bounds.left; worldPos[0] <= bounds.right; worldPos[0]++) {
// Check candidates in the reverse order they would have been
// drawn. This will determine what candiate's silhouette pixel
// would have been drawn at the point.
for (let d = candidateIDs.length - 1; d >= 0; d--) {
const id = candidateIDs[d];
const drawable = this._allDrawables[id];
if (drawable.isTouching(worldPos)) {
hits[id] = (hits[id] || 0) + 1;
break;
}
}
}
}
// Bias toward selecting anything over nothing
hits[RenderConstants.ID_NONE] = 0;
let hit = RenderConstants.ID_NONE;
for (const hitID in hits) {
if (Object.prototype.hasOwnProperty.call(hits, hitID) && (hits[hitID] > hits[hit])) {
hit = hitID;
}
}
return Number(hit);
}
/**
* @typedef DrawableExtraction
* @property {ImageData} data Raw pixel data for the drawable
* @property {number} x The x coordinate of the drawable's bounding box's top-left corner, in 'CSS pixels'
* @property {number} y The y coordinate of the drawable's bounding box's top-left corner, in 'CSS pixels'
* @property {number} width The drawable's bounding box width, in 'CSS pixels'
* @property {number} height The drawable's bounding box height, in 'CSS pixels'
*/
/**
* Return a drawable's pixel data and bounds in screen space.
* @param {int} drawableID The ID of the drawable to get pixel data for
* @return {DrawableExtraction} Data about the picked drawable
*/
extractDrawableScreenSpace (drawableID) {
const drawable = this._allDrawables[drawableID];
if (!drawable) throw new Error(`Could not extract drawable with ID ${drawableID}; it does not exist`);
this._doExitDrawRegion();
const nativeCenterX = this._nativeSize[0] * 0.5;
const nativeCenterY = this._nativeSize[1] * 0.5;
const scratchBounds = drawable.getFastBounds();
const canvas = this.canvas;
// Ratio of the screen-space scale of the stage's canvas to the "native size" of the stage
const scaleFactor = canvas.width / this._nativeSize[0];
// Bounds of the extracted drawable, in "canvas pixel space"
// (origin is 0, 0, destination is the canvas width, height).
const canvasSpaceBounds = new Rectangle();
canvasSpaceBounds.initFromBounds(
(scratchBounds.left + nativeCenterX) * scaleFactor,
(scratchBounds.right + nativeCenterX) * scaleFactor,
// in "canvas space", +y is down, but Rectangle methods assume bottom < top, so swap them
(nativeCenterY - scratchBounds.top) * scaleFactor,
(nativeCenterY - scratchBounds.bottom) * scaleFactor
);
canvasSpaceBounds.snapToInt();
// undo the transformation to transform the bounds, snapped to "canvas-pixel space", back to "Scratch space"
// We have to transform -> snap -> invert transform so that the "Scratch-space" bounds are snapped in
// "canvas-pixel space".
scratchBounds.initFromBounds(
(canvasSpaceBounds.left / scaleFactor) - nativeCenterX,
(canvasSpaceBounds.right / scaleFactor) - nativeCenterX,
nativeCenterY - (canvasSpaceBounds.top / scaleFactor),
nativeCenterY - (canvasSpaceBounds.bottom / scaleFactor)
);
const gl = this._gl;
// Set a reasonable max limit width and height for the bufferInfo bounds
const maxTextureSize = gl.getParameter(gl.MAX_TEXTURE_SIZE);
const clampedWidth = Math.min(MAX_EXTRACTED_DRAWABLE_DIMENSION, canvasSpaceBounds.width, maxTextureSize);
const clampedHeight = Math.min(MAX_EXTRACTED_DRAWABLE_DIMENSION, canvasSpaceBounds.height, maxTextureSize);
// Make a new bufferInfo since this._queryBufferInfo is limited to 480x360
const bufferInfo = twgl.createFramebufferInfo(gl, [{format: gl.RGBA}], clampedWidth, clampedHeight);
try {
twgl.bindFramebufferInfo(gl, bufferInfo);
// Limit size of viewport to the bounds around the target Drawable,
// and create the projection matrix for the draw.
gl.viewport(0, 0, clampedWidth, clampedHeight);
const projection = twgl.m4.ortho(
scratchBounds.left,
scratchBounds.right,
scratchBounds.top,
scratchBounds.bottom,
-1, 1
);
gl.clearColor(0, 0, 0, 0);
gl.clear(gl.COLOR_BUFFER_BIT);
this._drawThese([drawableID], ShaderManager.DRAW_MODE.straightAlpha, projection,
{
// Don't apply the ghost effect. TODO: is this an intentional design decision?
effectMask: ~ShaderManager.EFFECT_INFO.ghost.mask,
// We're doing this in screen-space, so the framebuffer dimensions should be those of the canvas in
// screen-space. This is used to ensure SVG skins are rendered at the proper resolution.
framebufferWidth: canvas.width,
framebufferHeight: canvas.height
});
const data = new Uint8Array(Math.floor(clampedWidth * clampedHeight * 4));
gl.readPixels(0, 0, clampedWidth, clampedHeight, gl.RGBA, gl.UNSIGNED_BYTE, data);
// readPixels can only read into a Uint8Array, but ImageData has to take a Uint8ClampedArray.
// We can share the same underlying buffer between them to avoid having to copy any data.
const imageData = new ImageData(new Uint8ClampedArray(data.buffer), clampedWidth, clampedHeight);
// On high-DPI devices, the canvas' width (in canvas pixels) will be larger than its width in CSS pixels.
// We want to return the CSS-space bounds,
// so take into account the ratio between the canvas' pixel dimensions and its layout dimensions.
// This is usually the same as 1 / window.devicePixelRatio, but if e.g. you zoom your browser window without
// the canvas resizing, then it'll differ.
const ratio = canvas.getBoundingClientRect().width / canvas.width;
return {
imageData,
x: canvasSpaceBounds.left * ratio,
y: canvasSpaceBounds.bottom * ratio,
width: canvasSpaceBounds.width * ratio,
height: canvasSpaceBounds.height * ratio
};
} finally {
gl.deleteFramebuffer(bufferInfo.framebuffer);
}
}
/**
* @typedef ColorExtraction
* @property {Uint8Array} data Raw pixel data for the drawable
* @property {int} width Drawable bounding box width
* @property {int} height Drawable bounding box height
* @property {object} color Color object with RGBA properties at picked location
*/
/**
* Return drawable pixel data and color at a given position
* @param {int} x The client x coordinate of the picking location.
* @param {int} y The client y coordinate of the picking location.
* @param {int} radius The client radius to extract pixels with.
* @return {?ColorExtraction} Data about the picked color
*/
extractColor (x, y, radius) {
this._doExitDrawRegion();
const scratchX = Math.round(this._nativeSize[0] * ((x / this._gl.canvas.clientWidth) - 0.5));
const scratchY = Math.round(-this._nativeSize[1] * ((y / this._gl.canvas.clientHeight) - 0.5));
const gl = this._gl;
twgl.bindFramebufferInfo(gl, this._queryBufferInfo);
const bounds = new Rectangle();
bounds.initFromBounds(scratchX - radius, scratchX + radius, scratchY - radius, scratchY + radius);
const pickX = scratchX - bounds.left;
const pickY = bounds.top - scratchY;
gl.viewport(0, 0, bounds.width, bounds.height);
const projection = twgl.m4.ortho(bounds.left, bounds.right, bounds.top, bounds.bottom, -1, 1);
gl.clearColor(...this._backgroundColor4f);
gl.clear(gl.COLOR_BUFFER_BIT);
this._drawThese(this._drawList, ShaderManager.DRAW_MODE.default, projection);
const data = new Uint8Array(Math.floor(bounds.width * bounds.height * 4));
gl.readPixels(0, 0, bounds.width, bounds.height, gl.RGBA, gl.UNSIGNED_BYTE, data);
const pixelBase = Math.floor(4 * ((pickY * bounds.width) + pickX));
const color = {
r: data[pixelBase],
g: data[pixelBase + 1],
b: data[pixelBase + 2],
a: data[pixelBase + 3]
};
if (this._debugCanvas) {
this._debugCanvas.width = bounds.width;
this._debugCanvas.height = bounds.height;
const ctx = this._debugCanvas.getContext('2d');
const imageData = ctx.createImageData(bounds.width, bounds.height);
imageData.data.set(data);
ctx.putImageData(imageData, 0, 0);
ctx.strokeStyle = 'black';
ctx.fillStyle = `rgba(${color.r}, ${color.g}, ${color.b}, ${color.a})`;
ctx.rect(pickX - 4, pickY - 4, 8, 8);
ctx.fill();
ctx.stroke();
}
return {
data: data,
width: bounds.width,
height: bounds.height,
color: color
};
}
/**
* Get the candidate bounding box for a touching query.
* @param {int} drawableID ID for drawable of query.
* @return {?Rectangle} Rectangle bounds for touching query, or null.
*/
_touchingBounds (drawableID) {
const drawable = this._allDrawables[drawableID];
/** @todo remove this once URL-based skin setting is removed. */
if (!drawable.skin || !drawable.skin.getTexture([100, 100])) return null;
const bounds = drawable.getFastBounds();
// Limit queries to the stage size.
bounds.clamp(this._xLeft, this._xRight, this._yBottom, this._yTop);
// Use integer coordinates for queries - weird things happen
// when you provide float width/heights to gl.viewport and projection.
bounds.snapToInt();
if (bounds.width === 0 || bounds.height === 0) {
// No space to query.
return null;
}
return bounds;
}
/**
* Filter a list of candidates for a touching query into only those that
* could possibly intersect the given bounds.
* @param {int} drawableID - ID for drawable of query.
* @param {Array<int>} candidateIDs - Candidates for touching query.
* @return {?Array< {id, drawable, intersection} >} Filtered candidates with useful data.
*/
_candidatesTouching (drawableID, candidateIDs) {
const bounds = this._touchingBounds(drawableID);
const result = [];
if (bounds === null) {
return result;
}
// iterate through the drawables list BACKWARDS - we want the top most item to be the first we check
for (let index = candidateIDs.length - 1; index >= 0; index--) {
const id = candidateIDs[index];
if (id !== drawableID) {
const drawable = this._allDrawables[id];
// Text bubbles aren't considered in "touching" queries
if (drawable.skin instanceof TextBubbleSkin) continue;
if (drawable.skin && drawable._visible) {
// Update the CPU position data
drawable.updateCPURenderAttributes();
const candidateBounds = drawable.getFastBounds();
// Push bounds out to integers. If a drawable extends out into half a pixel, that half-pixel still
// needs to be tested. Plus, in some areas we construct another rectangle from the union of these,
// and iterate over its pixels (width * height). Turns out that doesn't work so well when the
// width/height aren't integers.
candidateBounds.snapToInt();
if (bounds.intersects(candidateBounds)) {
result.push({
id,
drawable,
intersection: Rectangle.intersect(bounds, candidateBounds)
});
}
}
}
}
return result;
}
/**
* Helper to get the union bounds from a set of candidates returned from the above method
* @private
* @param {Array<object>} candidates info from _candidatesTouching
* @return {Rectangle} the outer bounding box union
*/
_candidatesBounds (candidates) {
return candidates.reduce((memo, {intersection}) => {
if (!memo) {
return intersection;
}
// store the union of the two rectangles in our static rectangle instance
return Rectangle.union(memo, intersection, __candidatesBounds);
}, null);
}
/**
* Update a drawable's skin.
* @param {number} drawableID The drawable's id.
* @param {number} skinId The skin to update to.
*/
updateDrawableSkinId (drawableID, skinId) {
const drawable = this._allDrawables[drawableID];
// TODO: https://github.com/LLK/scratch-vm/issues/2288
if (!drawable) return;
drawable.skin = this._allSkins[skinId];
}
/**
* Update a drawable's position.
* @param {number} drawableID The drawable's id.
* @param {Array.<number>} position The new position.
*/
updateDrawablePosition (drawableID, position) {
const drawable = this._allDrawables[drawableID];
// TODO: https://github.com/LLK/scratch-vm/issues/2288
if (!drawable) return;
drawable.updatePosition(position);
}
/**
* Update a drawable's direction.
* @param {number} drawableID The drawable's id.
* @param {number} direction A new direction.
*/
updateDrawableDirection (drawableID, direction) {
const drawable = this._allDrawables[drawableID];
// TODO: https://github.com/LLK/scratch-vm/issues/2288
if (!drawable) return;
drawable.updateDirection(direction);
}
/**
* Update a drawable's scale.
* @param {number} drawableID The drawable's id.
* @param {Array.<number>} scale A new scale.
*/
updateDrawableScale (drawableID, scale) {
const drawable = this._allDrawables[drawableID];
// TODO: https://github.com/LLK/scratch-vm/issues/2288
if (!drawable) return;
drawable.updateScale(scale);
}
/**
* Update a drawable's direction and scale together.
* @param {number} drawableID The drawable's id.
* @param {number} direction A new direction.
* @param {Array.<number>} scale A new scale.
*/
updateDrawableDirectionScale (drawableID, direction, scale) {
const drawable = this._allDrawables[drawableID];
// TODO: https://github.com/LLK/scratch-vm/issues/2288
if (!drawable) return;
drawable.updateDirection(direction);
drawable.updateScale(scale);
}
/**
* Update a drawable's visibility.
* @param {number} drawableID The drawable's id.
* @param {boolean} visible Will the drawable be visible?
*/
updateDrawableVisible (drawableID, visible) {
const drawable = this._allDrawables[drawableID];
// TODO: https://github.com/LLK/scratch-vm/issues/2288
if (!drawable) return;
drawable.updateVisible(visible);
}
/**
* Update a drawable's visual effect.
* @param {number} drawableID The drawable's id.
* @param {string} effectName The effect to change.
* @param {number} value A new effect value.
*/
updateDrawableEffect (drawableID, effectName, value) {
const drawable = this._allDrawables[drawableID];
// TODO: https://github.com/LLK/scratch-vm/issues/2288
if (!drawable) return;
drawable.updateEffect(effectName, value);
}
/**
* Update the position, direction, scale, or effect properties of this Drawable.
* @deprecated Use specific updateDrawable* methods instead.
* @param {int} drawableID The ID of the Drawable to update.
* @param {object.<string,*>} properties The new property values to set.
*/
updateDrawableProperties (drawableID, properties) {
const drawable = this._allDrawables[drawableID];
if (!drawable) {
/**
* @todo(https://github.com/LLK/scratch-vm/issues/2288) fix whatever's wrong in the VM which causes this, then add a warning or throw here.
* Right now this happens so much on some projects that a warning or exception here can hang the browser.
*/
return;
}
if ('skinId' in properties) {
this.updateDrawableSkinId(drawableID, properties.skinId);
}
drawable.updateProperties(properties);
}
/**
* Update the position object's x & y members to keep the drawable fenced in view.
* @param {int} drawableID - The ID of the Drawable to update.
* @param {Array.<number, number>} position to be fenced - An array of type [x, y]
* @return {Array.<number, number>} The fenced position as an array [x, y]
*/
getFencedPositionOfDrawable (drawableID, position) {
let x = position[0];
let y = position[1];
const drawable = this._allDrawables[drawableID];
if (!drawable) {
// @todo(https://github.com/LLK/scratch-vm/issues/2288) fix whatever's wrong in the VM which causes this, then add a warning or throw here.
// Right now this happens so much on some projects that a warning or exception here can hang the browser.
return [x, y];
}
const dx = x - drawable._position[0];
const dy = y - drawable._position[1];
const aabb = drawable._skin.getFenceBounds(drawable, __fenceBounds);
const inset = Math.floor(Math.min(aabb.width, aabb.height) / 2);
const sx = this._xRight - Math.min(FENCE_WIDTH, inset);
if (aabb.right + dx < -sx) {
x = Math.ceil(drawable._position[0] - (sx + aabb.right));
} else if (aabb.left + dx > sx) {
x = Math.floor(drawable._position[0] + (sx - aabb.left));
}
const sy = this._yTop - Math.min(FENCE_WIDTH, inset);
if (aabb.top + dy < -sy) {
y = Math.ceil(drawable._position[1] - (sy + aabb.top));
} else if (aabb.bottom + dy > sy) {
y = Math.floor(drawable._position[1] + (sy - aabb.bottom));
}
return [x, y];
}
/**
* Clear a pen layer.
* @param {int} penSkinID - the unique ID of a Pen Skin.
*/
penClear (penSkinID) {
const skin = /** @type {PenSkin} */ this._allSkins[penSkinID];
skin.clear();
}
/**
* Draw a point on a pen layer.
* @param {int} penSkinID - the unique ID of a Pen Skin.
* @param {PenAttributes} penAttributes - how the point should be drawn.
* @param {number} x - the X coordinate of the point to draw.
* @param {number} y - the Y coordinate of the point to draw.
*/
penPoint (penSkinID, penAttributes, x, y) {
const skin = /** @type {PenSkin} */ this._allSkins[penSkinID];
skin.drawPoint(penAttributes, x, y);
}
/**
* Draw a line on a pen layer.
* @param {int} penSkinID - the unique ID of a Pen Skin.
* @param {PenAttributes} penAttributes - how the line should be drawn.
* @param {number} x0 - the X coordinate of the beginning of the line.
* @param {number} y0 - the Y coordinate of the beginning of the line.
* @param {number} x1 - the X coordinate of the end of the line.
* @param {number} y1 - the Y coordinate of the end of the line.
*/
penLine (penSkinID, penAttributes, x0, y0, x1, y1) {
const skin = /** @type {PenSkin} */ this._allSkins[penSkinID];
skin.drawLine(penAttributes, x0, y0, x1, y1);
}
/**
* Stamp a Drawable onto a pen layer.
* @param {int} penSkinID - the unique ID of a Pen Skin.
* @param {int} stampID - the unique ID of the Drawable to use as the stamp.
*/
penStamp (penSkinID, stampID) {
const stampDrawable = this._allDrawables[stampID];
if (!stampDrawable) {
return;
}
const bounds = this._touchingBounds(stampID);
if (!bounds) {
return;
}
this._doExitDrawRegion();
const skin = /** @type {PenSkin} */ this._allSkins[penSkinID];
const gl = this._gl;
twgl.bindFramebufferInfo(gl, skin._framebuffer);
// Limit size of viewport to the bounds around the stamp Drawable and create the projection matrix for the draw.
gl.viewport(
(this._nativeSize[0] * 0.5) + bounds.left,
(this._nativeSize[1] * 0.5) - bounds.top,
bounds.width,
bounds.height
);
const projection = twgl.m4.ortho(bounds.left, bounds.right, bounds.top, bounds.bottom, -1, 1);
// Draw the stamped sprite onto the PenSkin's framebuffer.
this._drawThese([stampID], ShaderManager.DRAW_MODE.default, projection, {ignoreVisibility: true});
skin._silhouetteDirty = true;
}
/* ******
* Truly internal functions: these support the functions above.
********/
/**
* Build geometry (vertex and index) buffers.
* @private
*/
_createGeometry () {
const quad = {
a_position: {
numComponents: 2,
data: [
-0.5, -0.5,
0.5, -0.5,
-0.5, 0.5,
-0.5, 0.5,
0.5, -0.5,
0.5, 0.5
]
},
a_texCoord: {
numComponents: 2,
data: [
1, 0,
0, 0,
1, 1,
1, 1,
0, 0,
0, 1
]
}
};
this._bufferInfo = twgl.createBufferInfoFromArrays(this._gl, quad);
}
/**
* Respond to a change in the "native" rendering size. The native size is used by buffers which are fixed in size
* regardless of the size of the main render target. This includes the buffers used for queries such as picking and
* color-touching. The fixed size allows (more) consistent behavior across devices and presentation modes.
* @param {object} event - The change event.
* @private
*/
onNativeSizeChanged (event) {
const [width, height] = event.newSize;
const gl = this._gl;
const attachments = [
{format: gl.RGBA},
{format: gl.DEPTH_STENCIL}
];
if (!this._pickBufferInfo) {
this._pickBufferInfo = twgl.createFramebufferInfo(gl, attachments, MAX_TOUCH_SIZE[0], MAX_TOUCH_SIZE[1]);
}
/** @todo should we create this on demand to save memory? */
// A 480x360 32-bpp buffer is 675 KiB.
if (this._queryBufferInfo) {
twgl.resizeFramebufferInfo(gl, this._queryBufferInfo, attachments, width, height);
} else {
this._queryBufferInfo = twgl.createFramebufferInfo(gl, attachments, width, height);
}
}
/**
* Enter a draw region.
*
* A draw region is where multiple draw operations are performed with the
* same GL state. WebGL performs poorly when it changes state like blend
* mode. Marking a collection of state values as a "region" the renderer
* can skip superfluous extra state calls when it is already in that
* region. Since one region may be entered from within another a exit
* handle can also be registered that is called when a new region is about
* to be entered to restore a common inbetween state.
*
* @param {any} regionId - id of the region to enter
* @param {function} enter - handle to call when first entering a region
* @param {function} exit - handle to call when leaving a region
*/
enterDrawRegion (regionId, enter = regionId.enter, exit = regionId.exit) {
if (this._regionId !== regionId) {
this._doExitDrawRegion();
this._regionId = regionId;
enter();
this._exitRegion = exit;
}
}
/**
* Forcefully exit the current region returning to a common inbetween GL
* state.
*/
_doExitDrawRegion () {
if (this._exitRegion !== null) {
this._exitRegion();
}
this._exitRegion = null;
this._regionId = null;
}
/**
* Draw a set of Drawables, by drawable ID
* @param {Array<int>} drawables The Drawable IDs to draw, possibly this._drawList.
* @param {ShaderManager.DRAW_MODE} drawMode Draw normally, silhouette, etc.
* @param {module:twgl/m4.Mat4} projection The projection matrix to use.
* @param {object} [opts] Options for drawing
* @param {idFilterFunc} opts.filter An optional filter function.
* @param {object.<string,*>} opts.extraUniforms Extra uniforms for the shaders.
* @param {int} opts.effectMask Bitmask for effects to allow
* @param {boolean} opts.ignoreVisibility Draw all, despite visibility (e.g. stamping, touching color)
* @param {int} opts.framebufferWidth The width of the framebuffer being drawn onto. Defaults to "native" width
* @param {int} opts.framebufferHeight The height of the framebuffer being drawn onto. Defaults to "native" height
* @private
*/
_drawThese (drawables, drawMode, projection, opts = {}) {
const gl = this._gl;
let currentShader = null;
const framebufferSpaceScaleDiffers = (
'framebufferWidth' in opts && 'framebufferHeight' in opts &&
opts.framebufferWidth !== this._nativeSize[0] && opts.framebufferHeight !== this._nativeSize[1]
);
const numDrawables = drawables.length;
for (let drawableIndex = 0; drawableIndex < numDrawables; ++drawableIndex) {
const drawableID = drawables[drawableIndex];
// If we have a filter, check whether the ID fails
if (opts.filter && !opts.filter(drawableID)) continue;
const drawable = this._allDrawables[drawableID];
/** @todo check if drawable is inside the viewport before anything else */
// Hidden drawables (e.g., by a "hide" block) are not drawn unless
// the ignoreVisibility flag is used (e.g. for stamping or touchingColor).
if (!drawable.getVisible() && !opts.ignoreVisibility) continue;
// drawableScale is the "framebuffer-pixel-space" scale of the drawable, as percentages of the drawable's
// "native size" (so 100 = same as skin's "native size", 200 = twice "native size").
// If the framebuffer dimensions are the same as the stage's "native" size, there's no need to calculate it.
const drawableScale = framebufferSpaceScaleDiffers ? [
drawable.scale[0] * opts.framebufferWidth / this._nativeSize[0],
drawable.scale[1] * opts.framebufferHeight / this._nativeSize[1]
] : drawable.scale;
// If the skin or texture isn't ready yet, skip it.
if (!drawable.skin || !drawable.skin.getTexture(drawableScale)) continue;
const uniforms = {};
let effectBits = drawable.enabledEffects;
effectBits &= Object.prototype.hasOwnProperty.call(opts, 'effectMask') ? opts.effectMask : effectBits;
const newShader = this._shaderManager.getShader(drawMode, effectBits);
// Manually perform region check. Do not create functions inside a
// loop.
if (this._regionId !== newShader) {
this._doExitDrawRegion();
this._regionId = newShader;
currentShader = newShader;
gl.useProgram(currentShader.program);
twgl.setBuffersAndAttributes(gl, currentShader, this._bufferInfo);
Object.assign(uniforms, {
u_projectionMatrix: projection
});
}
Object.assign(uniforms,
drawable.skin.getUniforms(drawableScale),
drawable.getUniforms());
// Apply extra uniforms after the Drawable's, to allow overwriting.
if (opts.extraUniforms) {
Object.assign(uniforms, opts.extraUniforms);
}
if (uniforms.u_skin) {
twgl.setTextureParameters(
gl, uniforms.u_skin, {
minMag: drawable.skin.useNearest(drawableScale, drawable) ? gl.NEAREST : gl.LINEAR
}
);
}
twgl.setUniforms(currentShader, uniforms);
twgl.drawBufferInfo(gl, this._bufferInfo, gl.TRIANGLES);
}
this._regionId = null;
}
/**
* Get the convex hull points for a particular Drawable.
* To do this, calculate it based on the drawable's Silhouette.
* @param {int} drawableID The Drawable IDs calculate convex hull for.
* @return {Array<Array<number>>} points Convex hull points, as [[x, y], ...]
*/
_getConvexHullPointsForDrawable (drawableID) {
const drawable = this._allDrawables[drawableID];
const [width, height] = drawable.skin.size;
// No points in the hull if invisible or size is 0.
if (!drawable.getVisible() || width === 0 || height === 0) {
return [];
}
drawable.updateCPURenderAttributes();
/**
* Return the determinant of two vectors, the vector from A to B and the vector from A to C.
*
* The determinant is useful in this case to know if AC is counter-clockwise from AB.
* A positive value means that AC is counter-clockwise from AB. A negative value means AC is clockwise from AB.
*
* @param {Float32Array} A A 2d vector in space.
* @param {Float32Array} B A 2d vector in space.
* @param {Float32Array} C A 2d vector in space.
* @return {number} Greater than 0 if counter clockwise, less than if clockwise, 0 if all points are on a line.
*/
const determinant = function (A, B, C) {
// AB = B - A
// AC = C - A
// det (AB BC) = AB0 * AC1 - AB1 * AC0
return (((B[0] - A[0]) * (C[1] - A[1])) - ((B[1] - A[1]) * (C[0] - A[0])));
};
// This algorithm for calculating the convex hull somewhat resembles the monotone chain algorithm.
// The main difference is that instead of sorting the points by x-coordinate, and y-coordinate in case of ties,
// it goes through them by y-coordinate in the outer loop and x-coordinate in the inner loop.
// This gives us "left" and "right" hulls, whereas the monotone chain algorithm gives "top" and "bottom" hulls.
// Adapted from https://github.com/LLK/scratch-flash/blob/dcbeeb59d44c3be911545dfe54d46a32404f8e69/src/scratch/ScratchCostume.as#L369-L413
const leftHull = [];
const rightHull = [];
// While convex hull algorithms usually push and pop values from the list of hull points,
// here, we keep indices for the "last" point in each array. Any points past these indices are ignored.
// This is functionally equivalent to pushing and popping from a "stack" of hull points.
let leftEndPointIndex = -1;
let rightEndPointIndex = -1;
const _pixelPos = twgl.v3.create();
const _effectPos = twgl.v3.create();
let currentPoint;
// *Not* Scratch Space-- +y is bottom
// Loop over all rows of pixels, starting at the top
for (let y = 0; y < height; y++) {
_pixelPos[1] = y / height;
// We start at the leftmost point, then go rightwards until we hit an opaque pixel
let x = 0;
for (; x < width; x++) {
_pixelPos[0] = x / width;
EffectTransform.transformPoint(drawable, _pixelPos, _effectPos);
if (drawable.skin.isTouchingLinear(_effectPos)) {
currentPoint = [x, y];
break;
}
}
// If we managed to loop all the way through, there are no opaque pixels on this row. Go to the next one
if (x >= width) {
continue;
}
// Because leftEndPointIndex is initialized to -1, this is skipped for the first two rows.
// It runs only when there are enough points in the left hull to make at least one line.
// If appending the current point to the left hull makes a counter-clockwise turn,
// we want to append the current point. Otherwise, we decrement the index of the "last" hull point until the
// current point makes a counter-clockwise turn.
// This decrementing has the same effect as popping from the point list, but is hopefully faster.
while (leftEndPointIndex > 0) {
if (determinant(leftHull[leftEndPointIndex], leftHull[leftEndPointIndex - 1], currentPoint) > 0) {
break;
} else {
// leftHull.pop();
--leftEndPointIndex;
}
}
// This has the same effect as pushing to the point list.
// This "list head pointer" coding style leaves excess points dangling at the end of the list,
// but that doesn't matter; we simply won't copy them over to the final hull.
// leftHull.push(currentPoint);
leftHull[++leftEndPointIndex] = currentPoint;
// Now we repeat the process for the right side, looking leftwards for a pixel.
for (x = width - 1; x >= 0; x--) {
_pixelPos[0] = x / width;
EffectTransform.transformPoint(drawable, _pixelPos, _effectPos);
if (drawable.skin.isTouchingLinear(_effectPos)) {
currentPoint = [x, y];
break;
}
}
// Because we're coming at this from the right, it goes clockwise this time.
while (rightEndPointIndex > 0) {
if (determinant(rightHull[rightEndPointIndex], rightHull[rightEndPointIndex - 1], currentPoint) < 0) {
break;
} else {
--rightEndPointIndex;
}
}
rightHull[++rightEndPointIndex] = currentPoint;
}
// Start off "hullPoints" with the left hull points.
const hullPoints = leftHull;
// This is where we get rid of those dangling extra points.
hullPoints.length = leftEndPointIndex + 1;
// Add points from the right side in reverse order so all points are ordered clockwise.
for (let j = rightEndPointIndex; j >= 0; --j) {
hullPoints.push(rightHull[j]);
}
// Simplify boundary points using hull.js.
// TODO: Remove this; this algorithm already generates convex hulls.
return hull(hullPoints, Infinity);
}
/**
* Sample a "final" color from an array of drawables at a given scratch space.
* Will blend any alpha values with the drawables "below" it.
* @param {twgl.v3} vec Scratch Vector Space to sample
* @param {Array<Drawables>} drawables A list of drawables with the "top most"
* drawable at index 0
* @param {Uint8ClampedArray} dst The color3b space to store the answer in.
* @return {Uint8ClampedArray} The dst vector with everything blended down.
*/
static sampleColor3b (vec, drawables, dst) {
dst = dst || new Uint8ClampedArray(3);
dst.fill(0);
let blendAlpha = 1;
for (let index = 0; blendAlpha !== 0 && index < drawables.length; index++) {
/*
if (left > vec[0] || right < vec[0] ||
bottom > vec[1] || top < vec[0]) {
continue;
}
*/
Drawable.sampleColor4b(vec, drawables[index].drawable, __blendColor);
// Equivalent to gl.blendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA)
dst[0] += __blendColor[0] * blendAlpha;
dst[1] += __blendColor[1] * blendAlpha;
dst[2] += __blendColor[2] * blendAlpha;
blendAlpha *= (1 - (__blendColor[3] / 255));
}
// Backdrop could be transparent, so we need to go to the "clear color" of the
// draw scene (white) as a fallback if everything was alpha
dst[0] += blendAlpha * 255;
dst[1] += blendAlpha * 255;
dst[2] += blendAlpha * 255;
return dst;
}
/**
* @callback RenderWebGL#snapshotCallback
* @param {string} dataURI Data URI of the snapshot of the renderer
*/
/**
* @param {snapshotCallback} callback Function called in the next frame with the snapshot data
*/
requestSnapshot (callback) {
this._snapshotCallbacks.push(callback);
}
}
// :3
RenderWebGL.prototype.canHazPixels = RenderWebGL.prototype.extractDrawableScreenSpace;
/**
* Values for setUseGPU()
* @enum {string}
*/
RenderWebGL.UseGpuModes = {
/**
* Heuristically decide whether to use the GPU path, the CPU path, or a dynamic mixture of the two.
*/
Automatic: 'Automatic',
/**
* Always use the GPU path.
*/
ForceGPU: 'ForceGPU',
/**
* Always use the CPU path.
*/
ForceCPU: 'ForceCPU'
};
module.exports = RenderWebGL;