Fix endless loop in shader and make framerate adaptive

It seems forcing points outside the cardioid and bulb with a bad random
generator can take really long...
Also, now framerate adjusts based on time it takes to render frames.

1 files changed, 19 insertions, 2 deletions

diff --git a/BuddhaTest/src/BuddhaTest.cpp b/BuddhaTest/src/BuddhaTest.cpp
index 67971ea..88f9c9b 100644
--- a/BuddhaTest/src/BuddhaTest.cpp
+++ b/BuddhaTest/src/BuddhaTest.cpp
@@ -3,6 +3,7 @@
 #include <Helpers.h>

 #include <iostream>

 #include <vector>

+#include <chrono>

 

 void error_callback(int error, const char* description)

 {

@@ -138,21 +139,26 @@ int main(int argc, char * argv[])
     glUniform3ui(orbitLengthUniformHandle,settings.orbitLengthRed,settings.orbitLengthGreen,settings.orbitLengthBlue);

     glUniform1ui(widthUniformComputeHandle, settings.imageWidth);

     glUniform1ui(heightUniformComputeHandle, bufferHeight);

-    glUniform1ui(iterationsPerDispatchHandle, settings.iterationsPerFrame);

 

     glUseProgram(VertexAndFragmentShaders);

     GLint widthUniformFragmentHandle = glGetUniformLocation(VertexAndFragmentShaders, "width");

     GLint heightUniformFragmentHandle = glGetUniformLocation(VertexAndFragmentShaders, "height");

     glUniform1ui(widthUniformFragmentHandle, settings.imageWidth);

     glUniform1ui(heightUniformFragmentHandle, bufferHeight);

-

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

 

+    uint32_t iterationsPerFrame = 1;

+

+    Helpers::PIDController<float, uint32_t> pid{0.0f,0.0f,1e-6f};

+    const uint32_t targetFrameDuration{1000000/settings.targetFrameRate};

+

 	/* Loop until the user closes the window */

 	while (!glfwWindowShouldClose(window))

 	{

+        auto frameStart{std::chrono::high_resolution_clock::now()};

 		//let the compute shader do something

         glUseProgram(ComputeShader);

+        glUniform1ui(iterationsPerDispatchHandle, iterationsPerFrame);

         glDispatchCompute(settings.globalWorkGroupSizeX, settings.globalWorkGroupSizeY, settings.globalWorkGroupSizeZ);

 

         //before reading the values in the ssbo, we need a memory barrier:

@@ -181,6 +187,17 @@ int main(int argc, char * argv[])
 

 		/* Poll for and process events */

 		glfwPollEvents();

+        auto frameStop{std::chrono::high_resolution_clock::now()};

+        const auto dur{std::chrono::duration_cast<std::chrono::microseconds>(frameStop-frameStart)};

+        auto frameDuration{dur.count()};

+        if(frameDuration > 0)

+        {

+            const auto error{targetFrameDuration - frameDuration};

+            const auto pidOutput{pid.Update(frameDuration,error)};

+            iterationsPerFrame = std::max(1,static_cast<int>(pidOutput));

+

+            //std::cout << iterationsPerFrame << " " << pidOutput << std::endl;

+        }

 	}

 

     if(!settings.pngFilename.empty())