render_system.cpp

#pragma once

#include "render_system.hpp"
#define GLM_FORCE_RADIANS
#define GLM_FORCE_DEPTH_ZERO_TO_ONE
#include <glm/glm.hpp>
#include <glm/gtc/constants.hpp>

#include <stdexcept>
#include <array>
#include <cassert>

namespace lve {
	struct SimplePushConstantData {
		glm::mat4 modelMatrix{1.0f};
		glm::mat4 normalMatrix{1.0f};
	};

	RenderSystem::RenderSystem(LveDevice& device, VkRenderPass renderPass, VkDescriptorSetLayout globalSetLayout) : lveDevice(device) {
		createPipelineLayout(globalSetLayout);
		createPipeline(renderPass);
	}
	RenderSystem::~RenderSystem() {
		vkDestroyPipelineLayout(lveDevice.device(), pipelineLayout, nullptr);
	}

	void RenderSystem::createPipelineLayout(VkDescriptorSetLayout globalSetLayout) {
		VkPushConstantRange pushConstantRange{};
		pushConstantRange.stageFlags = VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT;
		pushConstantRange.offset = 0;
		pushConstantRange.size = sizeof(SimplePushConstantData);

		std::vector<VkDescriptorSetLayout>desciptorSetLayouts{globalSetLayout};

		VkPipelineLayoutCreateInfo pipelineLayoutInfo{};
		pipelineLayoutInfo.sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO;
		pipelineLayoutInfo.setLayoutCount = static_cast<uint32_t>(desciptorSetLayouts.size());
		pipelineLayoutInfo.pSetLayouts = desciptorSetLayouts.data();
		pipelineLayoutInfo.pushConstantRangeCount = 1;
		pipelineLayoutInfo.pPushConstantRanges = &pushConstantRange;
		if (vkCreatePipelineLayout(lveDevice.device(), &pipelineLayoutInfo, nullptr, &pipelineLayout) != VK_SUCCESS) {
			throw std::runtime_error("failed to create pipeline layout!");
		}
	}

	void RenderSystem::createPipeline(VkRenderPass renderPass) {
		assert(pipelineLayout != nullptr && "Cannot create pipeline before pipeline layout");
		PipelineConfigInfo pipelineConfig{};
		LvePipeline::defaultPipelineConfigInfo(pipelineConfig);
		pipelineConfig.renderPass = renderPass;
		pipelineConfig.pipelineLayout = pipelineLayout;
		lvePipeline = std::make_unique<LvePipeline>(
			lveDevice,
			"shaders/simple_shader.vert.spv",
			"shaders/simple_shader.frag.spv",
			pipelineConfig
		);
	}

	void RenderSystem::renderGameObjects(FrameInfo& frameInfo) {
		lvePipeline->bind(frameInfo.commandBuffer);

		vkCmdBindDescriptorSets(
			frameInfo.commandBuffer,
			VK_PIPELINE_BIND_POINT_GRAPHICS,
			pipelineLayout,
			0, 
			1, 
			&frameInfo.globalDescriptorSet,
			0, 
			nullptr
		);

		for (auto& keyValue : frameInfo.gameObjects) {
			auto & obj = keyValue.second;
			if(obj.model == nullptr) continue;
			SimplePushConstantData push{};
			auto modelMatrix = obj.transform.mat4();
			push.modelMatrix = modelMatrix;
			push.normalMatrix = obj.transform.normalMatrix();
			vkCmdPushConstants(frameInfo.commandBuffer, pipelineLayout, VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT, 0, sizeof(SimplePushConstantData), &push);
			obj.model->bind(frameInfo.commandBuffer);
			obj.model->draw(frameInfo.commandBuffer);
		}
	}
}