co-maps/libs/shaders/GL/route_dash.fsh.glsl
2025-11-22 13:58:55 +01:00

49 lines
1.4 KiB
GLSL

// Warning! Beware to use this shader. "discard" command may significally reduce performance.
// Unfortunately some CG algorithms cannot be implemented without discarding fragments from depth buffer.
layout (location = 0) in vec3 v_length;
layout (location = 1) in vec4 v_color;
layout (location = 0) out vec4 v_FragColor;
layout (binding = 0) uniform UBO
{
mat4 u_modelView;
mat4 u_projection;
mat4 u_pivotTransform;
vec4 u_routeParams;
vec4 u_color;
vec4 u_maskColor;
vec4 u_outlineColor;
vec4 u_fakeColor;
vec4 u_fakeOutlineColor;
vec2 u_fakeBorders;
vec2 u_pattern;
vec2 u_angleCosSin;
float u_arrowHalfWidth;
float u_opacity;
};
const float kAntialiasingThreshold = 0.92;
float alphaFromPattern(float curLen, float dashLen, float gapLen)
{
float len = dashLen + gapLen;
float offset = fract(curLen / len) * len;
return step(offset, dashLen);
}
void main()
{
if (v_length.x < v_length.z)
discard;
vec2 coefs = step(v_length.xx, u_fakeBorders);
coefs.y = 1.0 - coefs.y;
vec4 mainColor = mix(u_color, u_fakeColor, coefs.x);
mainColor = mix(mainColor, u_fakeColor, coefs.y);
vec4 color = mainColor + v_color;
color.a *= (1.0 - smoothstep(kAntialiasingThreshold, 1.0, abs(v_length.y))) *
alphaFromPattern(v_length.x, u_pattern.x, u_pattern.y);
color = vec4(mix(color.rgb, u_maskColor.rgb, u_maskColor.a), color.a);
v_FragColor = color;
}