OpenGL ES 3.0 Fragment Shader with Partial Color and Alpha Control

// version 300 es

precision mediump float; precision mediump int;

// Author: yh

uniform sampler2D uBaseTexture; uniform mediump float fUseAlpha; // 如果该只大于1则使用该值

#ifdef PARTIAL_COLOR uniform sampler2D uPartialMaskTexture; uniform int uIsPartialMask; uniform vec3 uTexTransformFactor; varying vec3 vPartialColor; #endif

in vec2 vTextureCoord0; in vec4 vVertexColor;

#ifdef ENABLE_FOG in vec4 vFogColor; #endif

out vec4 fragColor;

void main() { vec4 base = texture(uBaseTexture, vTextureCoord0);

#ifdef ALPHA_TEST if(base.a <= 0.0) discard; #endif

#ifdef PARTIAL_COLOR if(bool(uIsPartialMask)) { vec4 maskColor = texture(uPartialMaskTexture, vTextureCoord0*uTexTransformFactor.x + uTexTransformFactor.yz); vec3 col = base.rgb; col.r *= vPartialColor.r; col.g *= vPartialColor.g; col.b *= vPartialColor.b; base.rgb = mix(base.rgb, col.rgb, maskColor.a); } else { base.r *= vPartialColor.r; base.g *= vPartialColor.g; base.b *= vPartialColor.b; } #endif

vec4 col = base;

#ifndef DISABLE_AMBIENT_LIGHT col *= vVertexColor; #endif

#ifdef ENABLE_FOG col = mix(col, vFogColor, vFogColor.a); #endif

float al = base.a;
if (fUseAlpha >= 1.0)
{
    al = fUseAlpha - 1.0;
}

fragColor = vec4(base.rgb, al);

}