axmol/cocos/renderer/shaders/label_distanceNormal.frag

28 lines
808 B
GLSL

const char* label_distanceNormal_frag = R"(
#ifdef GL_ES
precision lowp float;
#endif
varying vec4 v_fragmentColor;
varying vec2 v_texCoord;
uniform vec4 u_textColor;
uniform sampler2D u_texture;
void main()
{
vec4 color = texture2D(u_texture, v_texCoord);
//the texture use dual channel 16-bit output for distance_map
//float dist = color.b+color.g/256.0;
// the texture use single channel 8-bit output for distance_map
float dist = color.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) * u_textColor.a;
gl_FragColor = v_fragmentColor * vec4(u_textColor.rgb,alpha);
}
)";