funny-animated-gif-from-pro.../shaders/fragment.glsl

32 lines
1 KiB
GLSL

/*
Copyright (C) 2021 hiimgoodpack
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#version 330 core
in vec2 vTexCoord;
uniform sampler2D aTexture0;
void main() {
/*
dot(vTexCoord, vTexCoord)
essentially does pow(length(gl_FragCoord.xy),2), but
(probably) more optimized
We're doing this since we don't want fragments outside a circle
*/
float alpha = dot(vTexCoord, vTexCoord) > 1 ? 1 : 0;
gl_FragColor = vec4(0, 0, 0, alpha);
}