Chronos::Engine::UniformBuffer Class Reference

This is a Uniform buffer for storing the uniform variables in the shaders. More...

#include <buffers.hpp>

Inheritance diagram for Chronos::Engine::UniformBuffer:

Collaboration diagram for Chronos::Engine::UniformBuffer:

Public Member Functions
void	create (Chronos::Engine::Device device)
	Creates the buffer and maps the memory.
void	update (VkExtent2D swapChainExtent, float x, float y, float rotation, float x_size, float y_size)
	Updates the buffer with the given information.
Public Member Functions inherited from Chronos::Engine::Buffer
void	create (Chronos::Engine::Device device, VkBufferUsageFlags flags, VkMemoryPropertyFlags properties)
	This is used to initialize the buffer.
void	copy (void *data, VkCommandPool commandPool)
	Copies the data to the buffer.
void	destroy ()
	Destroys the buffer and frees the memory.

Private Attributes
void *	data
	Temporary storage used to store the data before copying to the buffer.

Additional Inherited Members
Public Attributes inherited from Chronos::Engine::Buffer
VkBuffer	buffer
	The buffer.
VkDeviceSize	size
	The size of the buffer.
VkDeviceMemory	memory
	The device memory of the buffer.

Detailed Description

This is a Uniform buffer for storing the uniform variables in the shaders.

Currently used only for shapes properties like postition, size etc. Can be updated on the fly using the update function.

Definition at line 104 of file buffers.hpp.

Member Function Documentation

create()

void Chronos::Engine::UniformBuffer::create

(

Chronos::Engine::Device

device

)

Creates the buffer and maps the memory.

It uses the inherited function create to create the buffer

Parameters

device

The device on which the buffer should be stored.

Definition at line 73 of file buffers.cpp.

{
    size = sizeof(UniformBufferObject);
    Buffer::create(device, VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT,
    VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT
        | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT); // want to be visible to
                             // host and device
    vkMapMemory(device.device, memory, 0, size, 0, &data);
}

References Chronos::Engine::Buffer::create(), and Chronos::Engine::Device::device.

Here is the call graph for this function:

update()

void Chronos::Engine::UniformBuffer::update	(	VkExtent2D	swapChainExtent,
		float	x,
		float	y,
		float	rotation,
		float	x_size,
		float	y_size
	)

Updates the buffer with the given information.

It creates a UniformBufferObject. The entires in this struct are calculated using glm functions. We need the swapChainExtent to calculate the projection matrix so that the scale is correct even when resizing windows.

Parameters

swapChainExtent	The extent of the swap chain.
x	The x coordinate of the shape.
y	The y coordinate of the shape.
rotation	The rotation of the shape.
x_size	The x size of the shape.
y_size	The y size of the shape.

Definition at line 83 of file buffers.cpp.

{
    // This is where the shape parameters are updated
    UniformBufferObject ubo {};
    ubo.model = glm::translate(glm::mat4(1.0f), glm::vec3(y, -x, 0.0f));
    ubo.model = glm::rotate(
    ubo.model, glm::radians(rotation), glm::vec3(0.0f, 0.0f, 1.0f));
    ubo.model = glm::scale(ubo.model, glm::vec3(y_size, x_size, 1.0f));
    ubo.view = glm::lookAt(glm::vec3(0.0f, 0.0f, 0.1f),
    glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(1.0f, 0.0f, 0.0f));
    ubo.proj = glm::ortho(-1.0f, 1.0f,
    -(float)swapChainExtent.height / (float)swapChainExtent.width,
    (float)swapChainExtent.height / (float)swapChainExtent.width, -100.0f,
    100.0f);
    ubo.proj[1][1] *= -1;
    memcpy(data, &ubo, sizeof(ubo));
    LOG(4,
    "Uniform buffer object updated for buffer ["
        + std::to_string((uint64_t)buffer) + "]")
}

References LOG, and Chronos::Engine::UniformBufferObject::model.

Member Data Documentation

data

void* Chronos::Engine::UniformBuffer::data

private

Temporary storage used to store the data before copying to the buffer.

Definition at line 141 of file buffers.hpp.

---

The documentation for this class was generated from the following files:

• Source/Rendering/buffers.hpp
• Source/Rendering/buffers.cpp