Update documentation and clean code for Uniform Buffers, added time variable to descriptor set, preparing for Texture mapping.

src/entrypoint.cpp

@@ -1,5 +1,4 @@
 #include "entrypoint.h"
-#include "global.h"
 DeviceControl::devicelibrary deviceLibs;
 Debug::vulkandebuglibs debugController;
 Graphics::graphicspipeline graphicsPipeline;

src/entrypoint.h

@@ -3,6 +3,7 @@
 #include "debug/vulkandebuglibs.h"
 #include "graphics/graphicspipeline.h"
 #include "graphics/render.h"
+#include "global.h"
 class EntryApp {
   public: 
     static EntryApp& getInstance();

src/global.h

@@ -3,6 +3,7 @@
 #include <glm/detail/qualifier.hpp>
 #include <glm/ext/vector_float2.hpp>
 #include <glm/ext/vector_float3.hpp>
+#include <glm/fwd.hpp>
 #include <iostream>
 #include <vector>
 #include <optional>
@@ -29,11 +30,11 @@ namespace Global {
   extern VkDescriptorSetLayout descriptorSetLayout;
   extern uint32_t currentFrame;
   extern std::vector<VkDescriptorSet> descriptorSets;
-
   struct UniformBufferObject {
-    glm::mat4 model;
-    glm::mat4 view;
-    glm::mat4 proj;
+    float time;
+    alignas(16) glm::mat4 model;
+    alignas(16) glm::mat4 view;
+    alignas(16) glm::mat4 proj;
   };
   struct Vertex {
     glm::vec2 pos;

src/graphics/buffers.cpp

@@ -165,7 +165,7 @@ namespace Buffers {
   std::vector<uint16_t> bufferslibrary::getIndices() {
     return indices;
   }
-  
+// ------------------------------ Uniform Buffer Setup -------------------------------- //
   void bufferslibrary::createDescriptorSetLayout() {
     // Create a table of pointers to data, a Descriptor Set!
     VkDescriptorSetLayoutBinding uboLayoutBinding{};
@@ -187,10 +187,9 @@ namespace Buffers {
       throw std::runtime_error("Failed to create descriptor set layout!");
     }
   }
-  //void createMVPDescriptor() {
-    
-  //}
   void bufferslibrary::createUniformBuffers() {
+    // Map the uniform buffer to memory as a pointer we can use to write data to later. This stays mapped to memory for the applications lifetime.
+    // This technique is called "persistent mapping", not having to map the buffer every time we need to update it increases performance, though not free
     VkDeviceSize bufferSize = sizeof(Global::UniformBufferObject);
     
     uniformBuffers.resize(Global::MAX_FRAMES_IN_FLIGHT);
@@ -203,12 +202,16 @@ namespace Buffers {
     }
   }
   void bufferslibrary::updateUniformBuffer(uint32_t currentImage) {
+    // Update the uniform buffer every frame to change the position, but notably, use chrono to know exactly how much to move 
+    // so we aren't locked to the framerate as the world time.
+
     static auto startTime = std::chrono::high_resolution_clock::now();
     // Calculate the time in seconds since rendering has began to floating point precision.
     auto currentTime = std::chrono::high_resolution_clock::now();
     float time = std::chrono::duration<float, std::chrono::seconds::period>(currentTime - startTime).count();
 
     Global::UniformBufferObject ubo{};
+    ubo.time = time;
     // Modify the model projection transformation to rotate around the Z over time.
     ubo.model = glm::rotate(glm::mat4(1.0f), time * glm::radians(90.0f), glm::vec3(0.0f, 0.0f, 1.0f));
     // Modify the view transformation to look at the object from above at a 45 degree angle.
@@ -229,6 +232,7 @@ namespace Buffers {
     }
   }
   void bufferslibrary::createDescriptorPool() {
+    // Create a pool to be used to allocate descriptor sets.
     VkDescriptorPoolSize poolSize{};
     poolSize.type = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER;
     poolSize.descriptorCount = static_cast<uint32_t>(Global::MAX_FRAMES_IN_FLIGHT);

src/graphics/graphicspipeline.cpp

@@ -238,7 +238,8 @@ namespace Graphics {
     }
   }
   void graphicspipeline::createCommandPool() {
-
+    // Commands in Vulkan are not executed using function calls, you have to record the ops you wish to perform 
+    // to command buffers, pools manage the memory used by the buffer!
     Global::QueueFamilyIndices queueFamilyIndices = Global::findQueueFamilies(Global::physicalDevice);
 
     VkCommandPoolCreateInfo poolInfo{};

src/shaders/vertex.vert

@@ -1,6 +1,7 @@
 #version 450
 
 layout(binding = 0) uniform UniformBufferObject {
+    float time;
     mat4 model;
     mat4 view;
     mat4 proj;
@@ -14,6 +15,5 @@ layout(location = 0) out vec3 fragColor;
 
 void main() {
     gl_Position = ubo.proj * ubo.view * ubo.model * vec4(inPosition, 0.0, 1.0);
-    fragColor = inColor;
+    fragColor = inColor + sin(ubo.time*2);
 }
-