Graphics: Add gamma correction

src/Nazara/Graphics/PostProcessPipelinePass.cpp

@@ -0,0 +1,107 @@
+// Copyright (C) 2023 Jérôme "Lynix" Leclercq (lynix680@gmail.com)
+// This file is part of the "Nazara Engine - Graphics module"
+// For conditions of distribution and use, see copyright notice in Config.hpp
+
+#include <Nazara/Graphics/PostProcessPipelinePass.hpp>
+#include <Nazara/Graphics/AbstractViewer.hpp>
+#include <Nazara/Graphics/FrameGraph.hpp>
+#include <Nazara/Graphics/Graphics.hpp>
+#include <Nazara/Renderer/RenderFrame.hpp>
+#include <Nazara/Graphics/Debug.hpp>
+
+namespace Nz
+{
+	PostProcessPipelinePass::PostProcessPipelinePass(FramePipeline& owner, std::string passName, std::string shaderName) :
+	m_passName(std::move(passName)),
+	m_shader(nzsl::ShaderStageType::Fragment | nzsl::ShaderStageType::Vertex, std::move(shaderName)),
+	m_pipeline(owner)
+	{
+		RenderPipelineLayoutInfo layoutInfo;
+		layoutInfo.bindings.assign({
+			{
+				0, 0, 1,
+				ShaderBindingType::Sampler,
+				nzsl::ShaderStageType::Fragment
+			}
+		});
+
+		std::shared_ptr<RenderDevice> renderDevice = Graphics::Instance()->GetRenderDevice();
+		m_renderPipelineLayout = renderDevice->InstantiateRenderPipelineLayout(std::move(layoutInfo));
+		if (!m_renderPipelineLayout)
+			throw std::runtime_error("failed to instantiate postprocess RenderPipelineLayout");
+
+		m_onShaderUpdated.Connect(m_shader.OnShaderUpdated, [this](UberShader*)
+		{
+			BuildPipeline();
+		});
+		BuildPipeline();
+	}
+
+	void PostProcessPipelinePass::Prepare(RenderFrame& renderFrame)
+	{
+		if (m_nextRenderPipeline)
+		{
+			if (m_renderPipeline)
+				renderFrame.PushForRelease(std::move(m_renderPipeline));
+
+			m_renderPipeline = std::move(m_nextRenderPipeline);
+			m_rebuildFramePass = true;
+		}
+	}
+
+	FramePass& PostProcessPipelinePass::RegisterToFrameGraph(FrameGraph& frameGraph, std::size_t inputColorBufferIndex, std::size_t outputColorBufferIndex)
+	{
+		FramePass& postProcess = frameGraph.AddPass(m_passName);
+		postProcess.AddInput(inputColorBufferIndex);
+		postProcess.AddOutput(outputColorBufferIndex);
+
+		postProcess.SetExecutionCallback([&]()
+		{
+			return (m_rebuildFramePass) ? FramePassExecution::UpdateAndExecute : FramePassExecution::Execute;
+		});
+
+		postProcess.SetCommandCallback([this, inputColorBufferIndex](CommandBufferBuilder& builder, const FramePassEnvironment& env)
+		{
+			if (m_shaderBinding)
+				env.renderFrame.PushForRelease(std::move(m_shaderBinding));
+
+			auto& samplerCache = Graphics::Instance()->GetSamplerCache();
+
+			const auto& sourceTexture = env.frameGraph.GetAttachmentTexture(inputColorBufferIndex);
+			const auto& sampler = samplerCache.Get({});
+
+			m_shaderBinding = m_renderPipelineLayout->AllocateShaderBinding(0);
+			m_shaderBinding->Update({
+				{
+					0,
+					Nz::ShaderBinding::SampledTextureBinding {
+						sourceTexture.get(), sampler.get()
+					}
+				}
+			});
+
+			builder.SetScissor(env.renderRect);
+			builder.SetViewport(env.renderRect);
+
+			builder.BindRenderPipeline(*m_renderPipeline);
+			builder.BindRenderShaderBinding(0, *m_shaderBinding);
+
+			builder.Draw(3);
+
+			m_rebuildFramePass = false;
+		});
+
+		return postProcess;
+	}
+
+	void PostProcessPipelinePass::BuildPipeline()
+	{
+		std::shared_ptr<RenderDevice> renderDevice = Graphics::Instance()->GetRenderDevice();
+
+		RenderPipelineInfo pipelineInfo;
+		pipelineInfo.pipelineLayout = m_renderPipelineLayout;
+		pipelineInfo.shaderModules.push_back(m_shader.Get({}));
+
+		m_nextRenderPipeline = renderDevice->InstantiateRenderPipeline(pipelineInfo);
+	}
+}