mirror of
https://github.com/Ryujinx/Opentk.git
synced 2024-12-30 20:05:35 +00:00
66 lines
2.4 KiB
Plaintext
66 lines
2.4 KiB
Plaintext
|
#version 110
|
||
|
// www.OpenTK.net GLSL Julia Set (c) 2008 Christoph Brandtner
|
||
|
|
||
|
// uniforms from OpenGL
|
||
|
uniform sampler1D COLORTABLE;
|
||
|
uniform float CETX;
|
||
|
uniform float CETY;
|
||
|
uniform float SCALINGX;
|
||
|
uniform float SCALINGY;
|
||
|
uniform float OFFSETX;
|
||
|
uniform float OFFSETY;
|
||
|
|
||
|
// GLSL internal variables.
|
||
|
const int MAXIterations = 16; // must be greater than zero, 16 is a good blend between detail and speed
|
||
|
float XPos;
|
||
|
float YPos;
|
||
|
float XQuad;
|
||
|
float YQuad; // half precision floating point could be used on those 4 floats for speed, but will throw a warning.
|
||
|
int TableIndex;
|
||
|
int LoopCount;
|
||
|
|
||
|
// this function reduces duplicate code
|
||
|
void Iterate(void)
|
||
|
{
|
||
|
YPos = 2.0 * XPos * YPos + CETY;
|
||
|
XPos = XQuad - YQuad + CETX;
|
||
|
XQuad = pow(XPos, 2.0);
|
||
|
YQuad = pow(YPos, 2.0);
|
||
|
TableIndex++;
|
||
|
if ( (XQuad + YQuad) > 4.0 ) LoopCount = MAXIterations; // skip further iterations for this Pixel
|
||
|
LoopCount++;
|
||
|
}
|
||
|
|
||
|
// Shader entry point, this is executed per Pixel
|
||
|
void main(void)
|
||
|
{
|
||
|
XPos = gl_FragCoord.x / SCALINGX - OFFSETX;
|
||
|
YPos = gl_FragCoord.y / SCALINGY - OFFSETY;
|
||
|
XQuad = pow(XPos, 2.0);
|
||
|
YQuad = pow(YPos, 2.0);
|
||
|
TableIndex = -1;
|
||
|
LoopCount = 0;
|
||
|
// the loop is unrolled for SM 2.0 compatibility
|
||
|
if ( LoopCount <= MAXIterations ) Iterate(); // TableIndex==0
|
||
|
if ( LoopCount > 1 ) discard; // attempt to early-out, will affect ~1/3 of all Pixels
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate();
|
||
|
if ( LoopCount <= MAXIterations ) Iterate(); // TableIndex==16
|
||
|
float FinalTableIndex = float( TableIndex ) / float( MAXIterations );
|
||
|
|
||
|
gl_FragColor = texture1D( COLORTABLE, FinalTableIndex ); // lookup texture for output
|
||
|
// gl_FragColor.rgb = vec3(FinalTableIndex); // Debug: output greyscale
|
||
|
}
|