#version 150 core

uniform sampler2D DiffuseSampler;

in vec2 texCoord;
in vec2 oneTexel;

uniform vec2 InSize;

uniform vec2 BlurDir;
uniform float Radius;
uniform float Progress;

out vec4 outColor;

void main() {
    vec4 blurred = vec4(0.0);
    float progRadius = floor(Radius * Progress);
    for (float r = -progRadius; r <= progRadius; r += 1.0) {
        blurred += texture(DiffuseSampler, texCoord + oneTexel * r * BlurDir);
    }
    // force alpha to be 1.0 since otherwise areas with zero alpha turn black?
    outColor = vec4(blurred.rgb / (progRadius * 2.0 + 1.0), 1.0);
}