From c30a491b6cb20f13fa472b9a7cf9623789a77c2d Mon Sep 17 00:00:00 2001
From: Webster Sheets <webster@web-eworks.com>
Date: Tue, 5 Sep 2023 16:08:15 -0400
Subject: [PATCH] Editor: add MSAA to ViewportWindow

---
 src/editor/ViewportWindow.cpp | 27 +++++++++++++++++++--------
 src/editor/ViewportWindow.h   |  1 +
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/src/editor/ViewportWindow.cpp b/src/editor/ViewportWindow.cpp
index 6f83c044782..1dae2b2dc3f 100644
--- a/src/editor/ViewportWindow.cpp
+++ b/src/editor/ViewportWindow.cpp
@@ -6,6 +6,7 @@
 #include "editor/EditorApp.h"
 #include "graphics/Graphics.h"
 #include "graphics/RenderTarget.h"
+#include "graphics/Renderer.h"
 #include "graphics/Texture.h"
 
 #define IMGUI_DEFINE_MATH_OPERATORS
@@ -55,7 +56,7 @@ void ViewportWindow::Update(float deltaTime)
 		// Perform scene updates before rendering
 		OnUpdate(deltaTime);
 
-		ImVec2 size = ImGui::GetContentRegionAvail();
+		ImVec2 size = ImFloor(ImGui::GetContentRegionAvail());
 
 		m_viewportExtents.w = int(size.x);
 		m_viewportExtents.h = int(size.y);
@@ -68,7 +69,7 @@ void ViewportWindow::Update(float deltaTime)
 			// Draw our render target as the window "background"
 			// PiGui rendering happens after the contents of the texture are rendered
 			ImGui::GetWindowDrawList()->AddImageRounded(
-				ImTextureID(m_renderTarget->GetColorTexture()),
+				ImTextureID(m_resolveTarget->GetColorTexture()),
 				screenPos, screenPos + size,
 				ImVec2(0, 1), ImVec2(1, 0),
 				IM_COL32_WHITE,
@@ -82,9 +83,11 @@ void ViewportWindow::Update(float deltaTime)
 
 				r->SetRenderTarget(m_renderTarget.get());
 				r->SetViewport(m_viewportExtents);
-				r->ClearScreen(); // FIXME: add clear-command passing in immediate-state clear color
+				r->ClearScreen(Color::BLACK);
 
 				OnRender(r);
+
+				r->ResolveRenderTarget(m_renderTarget.get(), m_resolveTarget.get(), m_viewportExtents);
 			}
 
 			ImGui::BeginChild("##ViewportContainer", ImVec2(0, 0), false,
@@ -144,7 +147,7 @@ void ViewportWindow::Update(float deltaTime)
 
 void ViewportWindow::CreateRenderTarget()
 {
-	bool isValid = m_renderTarget &&
+	bool isValid = m_renderTarget && m_resolveTarget &&
 		m_renderTarget->GetDesc().width == m_viewportExtents.w &&
 		m_renderTarget->GetDesc().height == m_viewportExtents.h;
 
@@ -152,12 +155,20 @@ void ViewportWindow::CreateRenderTarget()
 		return;
 	}
 
-	Graphics::RenderTargetDesc rtdesc = Graphics::RenderTargetDesc(
+	Graphics::RenderTargetDesc rtDesc = Graphics::RenderTargetDesc(
+		m_viewportExtents.w, m_viewportExtents.h,
+		Graphics::TextureFormat::TEXTURE_RGB_888,
+		Graphics::TextureFormat::TEXTURE_DEPTH, false,
+		GetApp()->GetGraphicsSettings().requestedSamples
+	);
+
+	m_renderTarget.reset(GetApp()->GetRenderer()->CreateRenderTarget(rtDesc));
+
+	Graphics::RenderTargetDesc resolveDesc = Graphics::RenderTargetDesc(
 		m_viewportExtents.w, m_viewportExtents.h,
 		Graphics::TextureFormat::TEXTURE_RGB_888,
-		Graphics::TextureFormat::TEXTURE_DEPTH,
-		false, 0 // FIXME: multisample resolve for MSAA!
+		Graphics::TextureFormat::TEXTURE_NONE, true
 	);
 
-	m_renderTarget.reset(GetApp()->GetRenderer()->CreateRenderTarget(rtdesc));
+	m_resolveTarget.reset(GetApp()->GetRenderer()->CreateRenderTarget(resolveDesc));
 }
diff --git a/src/editor/ViewportWindow.h b/src/editor/ViewportWindow.h
index 31b79bd4b2b..281d17ff882 100644
--- a/src/editor/ViewportWindow.h
+++ b/src/editor/ViewportWindow.h
@@ -48,6 +48,7 @@ namespace Editor
 	private:
 
 		std::unique_ptr<Graphics::RenderTarget> m_renderTarget;
+		std::unique_ptr<Graphics::RenderTarget> m_resolveTarget;
 		Graphics::ViewportExtents m_viewportExtents;
 
 		bool m_viewportActive;