1、颜色加深
shader
//颜色加深
uniform sampler2D U_MainTexture;
uniform sampler2D U_SubTexture;
varying vec2 M_coord;
void main()
{
vec4 blendColor = texture2D(U_SubTexture, M_coord);
vec4 baseColor = texture2D(U_MainTexture, M_coord);
gl_FragColor = vec4(1.0) - (vec4(1.0) - baseColor) / blendColor;
}效果图
2、颜色减淡
shader
//颜色减淡
uniform sampler2D U_MainTexture;
uniform sampler2D U_SubTexture;
varying vec2 M_coord;
void main()
{
vec4 blendColor = texture2D(U_SubTexture, M_coord);
vec4 baseColor = texture2D(U_MainTexture, M_coord);
gl_FragColor = baseColor / (vec4(1.0) - blendColor);
}效果图
3、相加
shader
//相加
uniform sampler2D U_MainTexture;
uniform sampler2D U_SubTexture;
varying vec2 M_coord;
void main()
{
vec4 blendColor = texture2D(U_SubTexture, M_coord);
vec4 baseColor = texture2D(U_MainTexture, M_coord);
gl_FragColor = blendColor + baseColor;
}
4、相减
shader
//相减
uniform sampler2D U_MainTexture;
uniform sampler2D U_SubTexture;
varying vec2 M_coord;
void main()
{
vec4 blendColor = texture2D(U_SubTexture, M_coord);
vec4 baseColor = texture2D(U_MainTexture, M_coord);
gl_FragColor = vec4(baseColor.rgb - blendColor.rgb, 1.0);
}效果图
本文出自 “不会飞的纸飞机” 博客，请务必保留此出处http://douzhq.blog.51cto.com/12552184/1931105
基于Qt的OpenGL可编程管线学习（15）- 颜色加深、颜色减淡、想家相减
原文：http://douzhq.blog.51cto.com/12552184/1931105