#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;
    float uPhase;
    float uWidth;
};

layout(binding = 1) uniform sampler2D source;

void main() {
    vec4 tex = texture(source, qt_TexCoord0);
    float x = qt_TexCoord0.x * uWidth;
    // Soft reveal edge: fully visible 200px behind wave, fades out 50px ahead
    float mask = 1.0 - smoothstep(uPhase - 200.0, uPhase + 50.0, x);
    fragColor = tex * mask * qt_Opacity;
}