bgfx/3rdparty/openctm/tools/phong.frag
2012-10-07 20:41:18 -07:00

62 lines
2.3 KiB
GLSL

//-----------------------------------------------------------------------------
// Product: OpenCTM tools
// File: phong.frag
// Description: GLSL per-pixel phong shader - fragment shader
//-----------------------------------------------------------------------------
// Copyright (c) 2009-2010 Marcus Geelnard
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such, and must not
// be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source
// distribution.
//-----------------------------------------------------------------------------
uniform bool uUseTexture;
uniform sampler2D uTex;
varying vec3 vNormal;
varying vec3 vPos;
varying vec4 vColor;
void main()
{
vec3 n = normalize(vNormal);
// Calculate vertex color (vertex color * texture color)
vec4 color = vColor;
if(uUseTexture)
color *= texture2D(uTex, gl_TexCoord[0].st);
// Ambient term
// vec4 ambient = color * gl_LightSource[0].ambient;
vec4 ambient = color * gl_LightModel.ambient;
// Diffuse term
vec3 lightDir = normalize(gl_LightSource[0].position.xyz - vPos);
float NdotL = abs(dot(n, lightDir));
vec4 diffuse = color * gl_LightSource[0].diffuse * NdotL;
// Specular term
vec3 rVector = normalize(2.0 * n * dot(n, lightDir) - lightDir);
vec3 viewVector = normalize(-vPos);
float RdotV = dot(rVector, viewVector);
vec4 specular = vec4(0.0);
if(RdotV > 0.0)
specular = vec4(0.4, 0.4, 0.4, 1.0) * gl_LightSource[0].specular * pow(RdotV, 20.0);
gl_FragColor = ambient + diffuse + specular;
}