Decouple y and x value based on iteration. Should approximately square

teh available randomness!

2 files changed, 22 insertions, 21 deletions

diff --git a/BuddhaTest/Shaders/BuddhaCompute.glsl b/BuddhaTest/Shaders/BuddhaCompute.glsl
index 458a4e3..85d0cae 100644
--- a/BuddhaTest/Shaders/BuddhaCompute.glsl
+++ b/BuddhaTest/Shaders/BuddhaCompute.glsl
@@ -33,30 +33,17 @@ void addToColorAt(vec2 complex, uvec3 toAdd)
     addToColorOfCell(cell,toAdd);

 }

 

-/*

-vec2 hash2( uint n, out uint hash )

-{

-    // integer hash copied from Hugo Elias

-    n = (n << 13U) ^ n;

-    n = n * (n * n * 15731U + 789221U) + 1376312589U;

-    hash = n*n;

-    uvec2 k = n * uvec2(n,n*16807U);

-    return vec2( k & uvec2(0x7fffffffU))/float(0x7fffffff);

-}

-*/

-

 uint intHash(uint x) {

     x = ((x >> 16) ^ x) * 0x45d9f3bU;

     x = ((x >> 16) ^ x) * 0x45d9f3bU;

     x = (x >> 16) ^ x;

     return x;

 }

-vec2 hash2(uint n, out uint hash)

+

+float hash1(uint seed, out uint hash)

 {

-    uint ih =intHash(n);

-    hash = intHash(ih);

-    uvec2 k = uvec2(ih,hash);

-    return vec2(k & uvec2(0x7fffffffU))/float(0x7fffffff);

+    hash = intHash(seed);

+    return float(hash)/float(0xffffffffU);

 }

 

 vec2 compSqr(in vec2 v)

@@ -139,14 +126,17 @@ float isInMainBulb(vec2 v)
     return step(sqrRadius,0.062499999);

 }

 

-vec2 getStartValue(uint seed)

+vec2 getStartValue(uint seed, uint yDecoupler)

 {

     uint hash = seed;

 

     vec2 retval = vec2(0);

     for(int i = 0; i < 5; ++i)

     {

-        vec2 random = hash2(hash,hash);

+        float x = hash1(hash,hash);

+        hash = (hash ^ yDecoupler);

+        float y = hash1(hash,hash);

+        vec2 random = vec2(x,y);

         vec2 point = vec2(random.x * 3.5-2.5,random.y*1.55);

         float useThisPoint =1.0-(isInMainBulb(point) + isInMainCardioid(point));

         retval = mix(retval,point,useThisPoint);

@@ -197,8 +187,8 @@ void main() {
 

     //TODO: Check this once I've had some sleep. Anyhow, I'm using 1D, so y and z components globalInfocationID should be zero anyhow.

     uint seed = iterationCount * totalWorkers + gl_GlobalInvocationID.x + gl_GlobalInvocationID.y*totalWorkersPerDimension.x + gl_GlobalInvocationID.z*(totalWorkersPerDimension.x + totalWorkersPerDimension.y);

-

-    vec2 offset = getStartValue(seed);

+    uint yDecoupler = iterationCount;

+    vec2 offset = getStartValue(seed, yDecoupler);

 

     if(!isGoingToBeDrawn(offset))

         return;

diff --git a/BuddhaTest/src/BuddhaTest.cpp b/BuddhaTest/src/BuddhaTest.cpp
index c29a220..a03e8e8 100644
--- a/BuddhaTest/src/BuddhaTest.cpp
+++ b/BuddhaTest/src/BuddhaTest.cpp
@@ -126,9 +126,20 @@ int main(int argc, char * argv[])
 

     glClearColor(0.0f, 0.0f, 0.4f, 0.0f);

 

+    //uint32_t iterationsPerFrame = settings.globalWorkGroupSizeX*settings.globalWorkGroupSizeY*settings.globalWorkGroupSizeZ*settings.localWorkgroupSizeX*settings.localWorkgroupSizeY*settings.localWorkgroupSizeZ;

+    //bool bWarningShown{false};

+

 	/* Loop until the user closes the window */

 	while (!glfwWindowShouldClose(window))

 	{

+        //commented out, as with the new y-decoupling we will get more points in 2D even after we had all integer values for x.

+        //check if we are "done"

+        //if(iterationsPerFrame * iterationCount <= iterationsPerFrame && iterationCount > 1 && !bWarningShown)

+        //{

+        //    std::cout << "The program covered all possible integer values for starting point computation. Leaving it running will not improve the image any more." << std::endl;

+        //    bWarningShown = true;

+        //}

+

 		//let the compute shader do something

 		glUseProgram(ComputeShader);

         //increase iterationCount, which is used for pseudo random generation