#version 400
#extension GL_ARB_separate_shader_objects  : enable
#extension GL_ARB_shading_language_420pack : enable

layout(std140,binding = 1) uniform frag {
		mat3 scissorMat;
		mat3 paintMat;
		vec4 innerCol;
		vec4 outerCol;
		vec2 scissorExt;
		vec2 scissorScale;
		vec2 extent;
		float radius;
		float feather;
		float strokeMult;
		float strokeThr;
		int texType;
		int type;
	};
layout(binding = 2)uniform sampler2D tex;
layout(location = 0) in vec2 ftcoord;
layout(location = 1) in vec2 fpos;
layout(location = 0) out vec4 outColor;

float sdroundrect(vec2 pt, vec2 ext, float rad) {
	vec2 ext2 = ext - vec2(rad,rad);
	vec2 d = abs(pt) - ext2;
	return min(max(d.x,d.y),0.0) + length(max(d,0.0)) - rad;
}

// Scissoring
float scissorMask(vec2 p) {
	vec2 sc = (abs((scissorMat * vec3(p,1.0)).xy) - scissorExt);
	sc = vec2(0.5,0.5) - sc * scissorScale;
	return clamp(sc.x,0.0,1.0) * clamp(sc.y,0.0,1.0);
}
// Stroke - from [0..1] to clipped pyramid, where the slope is 1px.
float strokeMask() {
	return min(1.0, (1.0-abs(ftcoord.x*2.0-1.0))*strokeMult) * min(1.0, ftcoord.y);
}

void mainAA(void) {
   vec4 result;
	float scissor = scissorMask(fpos);
	float strokeAlpha = strokeMask();
	if (strokeAlpha < strokeThr) discard;
	if (type == 0) {			// Gradient
		// Calculate gradient color using box gradient
		vec2 pt = (paintMat * vec3(fpos,1.0)).xy;
		float d = clamp((sdroundrect(pt, extent, radius) + feather*0.5) / feather, 0.0, 1.0);
		vec4 color = mix(innerCol,outerCol,d);
		// Combine alpha
		color *= strokeAlpha * scissor;
		result = color;
	} else if (type == 1) {		// Image
		// Calculate color fron texture
		vec2 pt = (paintMat * vec3(fpos,1.0)).xy / extent;
		vec4 color = texture(tex, pt);
		if (texType == 1) color = vec4(color.xyz*color.w,color.w);
		if (texType == 2) color = vec4(color.x);
		// Apply color tint and alpha.
		color *= innerCol;
		// Combine alpha
		color *= strokeAlpha * scissor;
		result = color;
	} else if (type == 2) {		// Stencil fill
		result = vec4(1,1,1,1);
	} else if (type == 3) {		// Textured tris
		vec4 color = texture(tex, ftcoord);
		if (texType == 1) color = vec4(color.xyz*color.w,color.w);
		if (texType == 2) color = vec4(color.x);
		color *= scissor;
		result = color * innerCol;
	}
	outColor = result;
}
void main(void) {
   vec4 result;
	float scissor = scissorMask(fpos);
	float strokeAlpha = 1.0;
	if (type == 0) {			// Gradient
		// Calculate gradient color using box gradient
		vec2 pt = (paintMat * vec3(fpos,1.0)).xy;
		float d = clamp((sdroundrect(pt, extent, radius) + feather*0.5) / feather, 0.0, 1.0);
		vec4 color = mix(innerCol,outerCol,d);
		// Combine alpha
		color *= strokeAlpha * scissor;
		result = color;
	} else if (type == 1) {		// Image
		// Calculate color fron texture
		vec2 pt = (paintMat * vec3(fpos,1.0)).xy / extent;
		vec4 color = texture(tex, pt);
		if (texType == 1) color = vec4(color.xyz*color.w,color.w);
		if (texType == 2) color = vec4(color.x);
		// Apply color tint and alpha.
		color *= innerCol;
		// Combine alpha
		color *= strokeAlpha * scissor;
		result = color;
	} else if (type == 2) {		// Stencil fill
		result = vec4(1,1,1,1);
	} else if (type == 3) {		// Textured tris
		vec4 color = texture(tex, ftcoord);
		if (texType == 1) color = vec4(color.xyz*color.w,color.w);
		if (texType == 2) color = vec4(color.x);
		color *= scissor;
		result = color * innerCol;
	}
	outColor = result;
}