From d5952ba0431115e175f59da34a4b5adc328937cf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=BCrg=20Lehni?= <juerg@scratchdisk.com>
Date: Wed, 1 Jun 2011 20:21:25 +0100
Subject: [PATCH] Implement HSB blend modes.
---
src/util/BlendMode.js | 46 +++++++++++++++++++++++++++++++++----------
1 file changed, 36 insertions(+), 10 deletions(-)
diff --git a/src/util/BlendMode.js b/src/util/BlendMode.js
index e314ebc1..5eb4da3c 100644
--- a/src/util/BlendMode.js
+++ b/src/util/BlendMode.js
@@ -49,9 +49,30 @@ var BlendMode = {
min = Math.min,
max = Math.max,
abs = Math.abs,
- sr, sb, sg, sa, // source
- br, bb, bg, ba, // backdrop
- dr, dg, db; // destination
+ sr, sg, sb, sa, // source
+ br, bg, bb, ba, // backdrop
+ dr, dg, db, // destination
+ hsb = [],
+ // lookup table with indices for each hsb blend mode and hsb
+ // component inside the hsb table: 0 = source, 1 = backdrop
+ hsbIndices = {
+ hue: [0, 1, 1],
+ saturation: [1, 0, 1],
+ luminosity: [1, 1, 0],
+ color: [0, 0, 1]
+ }[blendMode];
+
+ function processHsb() {
+ hsb[0] = Color.RGBtoHSB(sr / 255, sg / 255, sb / 255);
+ hsb[1] = Color.RGBtoHSB(br / 255, bg / 255, bb / 255);
+ var rgb = Color.HSBtoRGB(
+ hsb[hsbIndices[0]][0],
+ hsb[hsbIndices[1]][1],
+ hsb[hsbIndices[2]][2]);
+ dr = rgb[0] * 255;
+ dg = rgb[1] * 255;
+ db = rgb[2] * 255;
+ }
var modes = {
multiply: function() {
@@ -74,12 +95,12 @@ var BlendMode = {
},
'soft-light': function() {
- var d = sr * br / 255;
- dr = d + br * (255 - (255 - br) * (255 - sr) / 255 - d) / 255;
- d = sg * bg / 255;
- dg = d + bg * (255 - (255 - bg) * (255 - sg) / 255 - d) / 255;
- d = sb * bb / 255;
- db = d + bb * (255 - (255 - bb) * (255 - sb) / 255 - d) / 255;
+ var t = sr * br / 255;
+ dr = t + br * (255 - (255 - br) * (255 - sr) / 255 - t) / 255;
+ t = sg * bg / 255;
+ dg = t + bg * (255 - (255 - bg) * (255 - sg) / 255 - t) / 255;
+ t = sb * bb / 255;
+ db = t + bb * (255 - (255 - bb) * (255 - sb) / 255 - t) / 255;
},
'hard-light': function() {
@@ -130,7 +151,12 @@ var BlendMode = {
db = bb + sb * (255 - bb - bb) / 255;
},
- // TODO: Missing: hue, saturation, color, luminosity
+ // HSB modes:
+
+ hue: processHsb,
+ saturation: processHsb,
+ luminosity: processHsb,
+ color: processHsb,
// TODO: Not in Illustrator:
add: function() {