From af65c60844d499ec879d83454587be167edc9456 Mon Sep 17 00:00:00 2001
From: Emanuel Rabina <emanuelrabina@gmail.com>
Date: Mon, 6 May 2024 23:01:36 +1200
Subject: [PATCH] Fix render to screen when ImGui windows disabled

---
 .../redhorizon/engine/Application.groovy      | 28 ++++++-------------
 .../engine/graphics/imgui/ImGuiLayer.groovy   |  8 ++++++
 .../graphics/pipeline/RenderPipeline.groovy   | 14 ++++------
 3 files changed, 23 insertions(+), 27 deletions(-)

diff --git a/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/Application.groovy b/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/Application.groovy
index 5af087ee..cc13186e 100644
--- a/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/Application.groovy
+++ b/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/Application.groovy
@@ -170,26 +170,16 @@ class Application implements EventTarget {
 		engine.waitUntilStopped()
 
 		// Check we closed everything
-		var activeFramebuffers = debugOverlay.activeFramebuffers.get()
-		if (activeFramebuffers > 0) {
-			logger.debug('Not all active framebuffers closed')
-		}
-		var activeMeshes = debugOverlay.activeMeshes.get()
-		if (activeMeshes > 0) {
-			logger.debug('Not all meshes closed, {} remaining', activeMeshes)
-		}
-		var activeTextures = debugOverlay.activeTextures.get()
-		if (activeMeshes > 0) {
-			logger.debug('Not all textures closed, {} remaining', activeTextures)
-		}
-		var activeSources = debugOverlay.activeSources.get()
-		if (activeMeshes > 0) {
-			logger.debug('Not all sources closed, {} remaining', activeSources)
-		}
-		var activeBuffers = debugOverlay.activeBuffers.get()
-		if (activeMeshes > 0) {
-			logger.debug('Not all buffers closed, {} remaining', activeBuffers)
+		var check = { int resourceCount, String resourceName ->
+			if (resourceCount > 0) {
+				logger.warn("Not all ${resourceName} closed, {} remaining", resourceCount)
+			}
 		}
+		check(debugOverlay.activeFramebuffers.get(), 'framebuffers')
+		check(debugOverlay.activeMeshes.get(), 'meshes')
+		check(debugOverlay.activeTextures.get(), 'textures')
+		check(debugOverlay.activeSources.get(), 'sources')
+		check(debugOverlay.activeBuffers.get(), 'buffers')
 	}
 
 	/**
diff --git a/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/graphics/imgui/ImGuiLayer.groovy b/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/graphics/imgui/ImGuiLayer.groovy
index 532a436f..dd389738 100644
--- a/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/graphics/imgui/ImGuiLayer.groovy
+++ b/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/graphics/imgui/ImGuiLayer.groovy
@@ -192,6 +192,14 @@ class ImGuiLayer implements AutoCloseable, InputSource {
 		imGuiGl3.renderDrawData(ImGui.getDrawData())
 	}
 
+	/**
+	 * Return whether or not ImGui is the render target.
+	 */
+	boolean isEnabled() {
+
+		return drawUiElements
+	}
+
 	/**
 	 * Build the docking window into which the app will be rendered.
 	 */
diff --git a/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/graphics/pipeline/RenderPipeline.groovy b/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/graphics/pipeline/RenderPipeline.groovy
index 158b480f..d191efff 100644
--- a/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/graphics/pipeline/RenderPipeline.groovy
+++ b/redhorizon-engine/source/nz/net/ultraq/redhorizon/engine/graphics/pipeline/RenderPipeline.groovy
@@ -58,6 +58,7 @@ class RenderPipeline implements Closeable {
 
 	private final Mesh fullScreenQuad
 	private final List<RenderPass> renderPasses = []
+	private ScreenRenderPass screenRenderPass
 
 	/**
 	 * Constructor, configure the rendering pipeline.
@@ -120,11 +121,11 @@ class RenderPipeline implements Closeable {
 			}
 
 		// Final pass to emit the result to the screen
-		renderPasses << new ScreenRenderPass(
+		screenRenderPass = new ScreenRenderPass(
 			renderer.createShader(new ScreenShader()),
-			!config.startWithChrome,
 			window
 		)
+		renderPasses << screenRenderPass
 	}
 
 	/**
@@ -136,6 +137,8 @@ class RenderPipeline implements Closeable {
 		imGuiLayer.frame { ->
 			renderer.clear()
 
+			screenRenderPass.enabled = !imGuiLayer.enabled
+
 			// Perform all rendering passes
 			var sceneResult = renderPasses.inject(null) { lastResult, renderPass ->
 				if (renderPass.enabled) {
@@ -247,15 +250,10 @@ class RenderPipeline implements Closeable {
 		/**
 		 * Constructor, create a basic material that covers the screen yet responds
 		 * to changes in output/window resolution.
-		 *
-		 * @param shader
-		 * @param enabled
-		 * @param window
 		 */
-		ScreenRenderPass(Shader shader, boolean enabled, Window window) {
+		ScreenRenderPass(Shader shader, Window window) {
 
 			this.shader = shader
-			this.enabled = enabled
 
 			transform.set(calculateScreenModelMatrix(window.framebufferSize, window.targetResolution))
 			window.on(FramebufferSizeEvent) { event ->