enve/examples/shaderEffects/eDots.frag
2020-03-31 17:04:51 +02:00

61 lines
1.9 KiB
GLSL
Executable File

// enve - 2D animations software
// Copyright (C) 2016-2020 Maurycy Liebner
// 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 <http://www.gnu.org/licenses/>.
#version 330 core
layout(location = 0) out vec4 fragColor;
in vec2 texCoord;
layout(pixel_center_integer) in vec4 gl_FragCoord;
uniform sampler2D texture;
uniform vec2 translate;
uniform float dotDistance;
uniform float dotRadius;
uniform float opacity;
uniform vec2 scenePos;
void main(void) {
bool inDot;
float mixAlpha;
vec2 transformedCoord = scenePos - translate + gl_FragCoord.xy;
vec2 dotID = floor(transformedCoord/dotDistance + 0.5);
vec2 posInDot = transformedCoord - dotID*dotDistance;
float distToCenter = sqrt(posInDot.x*posInDot.x +
posInDot.y*posInDot.y);
float distToEdge = distToCenter - sqrt(dotRadius*dotRadius);
if(distToEdge > 0.f) {
inDot = false;
} else {
distToEdge = abs(distToEdge);
inDot = true;
if(distToEdge < 1.f) {
mixAlpha = opacity + distToEdge*(1. - opacity);
} else {
mixAlpha = 1.f;
}
}
vec4 texCol = texture2D(texture, texCoord);
if(inDot) {
fragColor = vec4(mixAlpha*texCol.rgb, mixAlpha*texCol.a);
} else {
fragColor = vec4(opacity*texCol.rgb, opacity*texCol.a);
}
}