prosperon/source/shaders/particle.sglsl

@vs vs
in vec2 vertex;
in vec2 apos;
in float angle;
in vec2 scale;
in vec4 vc;

out vec4 fcolor;
out vec2 uv;

uniform vs_p { mat4 proj; };

void main()
{
  fcolor = vc;
  uv = vertex;
  vec2 v = vertex - 0.5;
  vec2 p = vec2(
    cos(angle)*v.x-sin(angle)*v.y,
    sin(angle)*v.x+cos(angle)*v.y
  );
  p += 0.5;
  p *= scale;
  p += apos;

  gl_Position = proj * vec4(p, 0.0, 1.0);
}
@end

@fs fs
in vec4 fcolor;
out vec4 color;

in vec2 uv;
uniform texture2D image;
uniform sampler smp;

void main()
{
  color = texture(sampler2D(image,smp),uv);
  color *= fcolor;
}
@end

@program particle vs fs