axmol/core/renderer/shaders/label_distanceFieldGlow.frag

32 lines
849 B
GLSL

#version 310 es
precision highp float;
precision highp int;
layout(location = 0) in vec4 v_fragmentColor;
layout(location = 1) in vec2 v_texCoord;
layout(binding = 0) uniform sampler2D u_tex0;
layout(std140, binding = 0) uniform fs_ub {
vec4 u_effectColor;
vec4 u_textColor;
};
layout(location = 0) out vec4 FragColor;
void main()
{
float dist = texture(u_tex0, v_texCoord).a;
//TODO: Implementation 'fwidth' for glsl 1.0
//float width = fwidth(dist);
//assign width for constant will lead to a little bit fuzzy,it's temporary measure.
float width = 0.04;
float alpha = smoothstep(0.5-width, 0.5+width, dist);
//glow
float mu = smoothstep(0.5, 1.0, sqrt(dist));
vec4 color = u_effectColor*(1.0-alpha) + u_textColor*alpha;
FragColor = v_fragmentColor * vec4(color.rgb, max(alpha,mu)*color.a);
}