#version 440

layout(location = 0) in vec2 qt_TexCoord0;
layout(location = 0) out vec4 fragColor;

layout(std140, binding = 0) uniform buf {
    mat4 qt_Matrix;
    float qt_Opacity;
    vec2 size;
    vec4 radii;
    vec4 color;
};

layout(binding = 1) uniform sampler2D source;

void main() {
    vec2 p = qt_TexCoord0 * size - size * 0.5;
    float radius = p.x < 0.0 ? (p.y < 0.0 ? radii.x : radii.w) : (p.y < 0.0 ? radii.y : radii.z);
    vec2 q = abs(p) - (size * 0.5 - radius);
    float d = length(max(q, 0.0)) + min(max(q.x, q.y), 0.0) - radius;
    float mask = 1.0 - smoothstep(-0.5, 0.5, d);

    vec4 content = texture(source, qt_TexCoord0);
    vec4 blended = content + color * (1.0 - content.a);
    fragColor = blended * mask * qt_Opacity;
}