fragmentshader.qml Example File
particles/customparticle/content/fragmentshader.qml
import QtQuick 2.0
import QtQuick.Particles 2.0
ParticleSystem {
id: root
width: 320
height: 480
Rectangle {
z: -1
anchors.fill: parent
color: "black"
Text {
anchors.bottom: parent.bottom
anchors.horizontalCenter: parent.horizontalCenter
font.pixelSize: 14
color: "white"
text: "It's all in the fragment shader."
}
}
Emitter {
emitRate: 400
lifeSpan: 8000
size: 24
sizeVariation: 16
velocity: PointDirection {x: root.width/10; y: root.height/10;}
acceleration: PointDirection {x: -root.width/40; y: -root.height/40; xVariation: -root.width/20; yVariation: -root.width/20}
}
CustomParticle {
vertexShader:"
uniform lowp float qt_Opacity;
varying lowp float fFade;
varying highp vec2 fPos;
void main() {
qt_TexCoord0 = qt_ParticleTex;
highp float size = qt_ParticleData.z;
highp float endSize = qt_ParticleData.w;
highp float t = (qt_Timestamp - qt_ParticleData.x) / qt_ParticleData.y;
highp float currentSize = mix(size, endSize, t * t);
if (t < 0. || t > 1.)
currentSize = 0.;
highp vec2 pos = qt_ParticlePos
- currentSize / 2. + currentSize * qt_ParticleTex // adjust size
+ qt_ParticleVec.xy * t * qt_ParticleData.y // apply velocity vector..
+ 0.5 * qt_ParticleVec.zw * pow(t * qt_ParticleData.y, 2.);
gl_Position = qt_Matrix * vec4(pos.x, pos.y, 0, 1);
highp float fadeIn = min(t * 20., 1.);
highp float fadeOut = 1. - max(0., min((t - 0.75) * 4., 1.));
fFade = fadeIn * fadeOut * qt_Opacity;
fPos = vec2(pos.x/320., pos.y/480.);
}
"
fragmentShader: "
varying highp vec2 fPos;
varying lowp float fFade;
varying highp vec2 qt_TexCoord0;
void main() {//*2 because this generates dark colors mostly
highp vec2 circlePos = qt_TexCoord0*2.0 - vec2(1.0,1.0);
highp float dist = length(circlePos);
highp float circleFactor = max(min(1.0 - dist, 1.0), 0.0);
gl_FragColor = vec4(fPos.x*2.0 - fPos.y, fPos.y*2.0 - fPos.x, fPos.x*fPos.y*2.0, 0.0) * circleFactor * fFade;
}"
}
}