#version 310 es precision highp float; precision highp int; /* Created by guanghui on 4/8/14. http://www.idevgames.com/forums/thread-3010.html */ layout(location = TEXCOORD0) in vec2 v_texCoord; layout(location = COLOR0) in vec4 v_color; layout(binding = 0) uniform sampler2D u_tex0; layout(std140) uniform fs_ub { vec3 u_outlineColor; float u_threshold; float u_radius; }; layout(location = SV_Target0) out vec4 FragColor; void main() { float radius = u_radius; vec4 accum = vec4(0.0); vec4 normal = vec4(0.0); normal = texture(u_tex0, vec2(v_texCoord.x, v_texCoord.y)); accum += texture(u_tex0, vec2(v_texCoord.x - radius, v_texCoord.y - radius)); accum += texture(u_tex0, vec2(v_texCoord.x + radius, v_texCoord.y - radius)); accum += texture(u_tex0, vec2(v_texCoord.x + radius, v_texCoord.y + radius)); accum += texture(u_tex0, vec2(v_texCoord.x - radius, v_texCoord.y + radius)); accum *= u_threshold; accum.rgb = u_outlineColor * accum.a; accum.a = 1.0; normal = ( accum * (1.0 - normal.a)) + (normal * normal.a); FragColor = v_color * normal; }