LearnOpenGL/Framebuffers.fs

75 lines
1.7 KiB
GLSL

#version 460 core
out vec4 FragColor;
in vec2 TexCoords;
uniform sampler2D screenTexure;
const float offset = 1.0/ 300.0;
void main(){
FragColor = texture(screenTexure, TexCoords);
// Inversion filter
//FragColor = vec4( vec3 (1.0 - texture(screenTexure, TexCoords) ), 1.0) ;
//grayscale
/*
FragColor = texture(screenTexure, TexCoords);
float average = (FragColor.r + FragColor.g + FragColor.b) / 3.0;
FragColor = vec4(average, average, average, 1.0);
*/
// physically accurate grayscale
// FragColor = texture(screenTexure, TexCoords);
// float average = 0.2126 * FragColor.r + 0.7152 * FragColor.g + 0.0722 * FragColor.b;
// FragColor = vec4(average,average,average, 1.0);
vec2 offset[9] = vec2[] (
vec2(-offset, offset), // top-left
vec2(0.0f, offset), // top-center
vec2(offset, offset), // top-right
vec2(-offset, 0.0f), // center-left
vec2(0.0f, 0.0f), // center-center
vec2(offset, 0.0f), // center-right
vec2(-offset, -offset), // bottom-left
vec2(0.0f, -offset), // bottom-center
vec2(offset, -offset) // bottom-right
);
// sharpen
/*float kernel[9] = float[](
-1, -1, -1,
-1, 9, -1,
-1, -1, -1
);*/
// blur
/* float kernel[9] = float[](
1.0 /16, 2.0 /16, 1.0 /16,
2.0 /16, 4.0 /16, 2.0 /16,
1.0 /16, 2.0 /16, 1.0 /16
);*/
// Edge-detection
/* float kernel[9] = float[] (
1, 1, 1,
1, -8, 1,
1, 1, 1
);
vec3 sampleTex[9];
for (int i= 0; i < 9; i++) {
sampleTex[i] = vec3(texture(screenTexure, TexCoords.st + offset[i]));
}
vec3 col = vec3(0.0);
for (int i = 0; i < 9; i++) {
col += sampleTex[i] * kernel[i];
}
FragColor = vec4(col, 1.0);
*/
}