Change the 2D matrix generation to query the coordinate convention from the draw context

Common/GPU/D3D11/thin3d_d3d11.cpp

@@ -259,6 +259,8 @@ D3D11DrawContext::D3D11DrawContext(ID3D11Device *device, ID3D11DeviceContext *de
 	// We no longer support Windows Phone.
 	_assert_(featureLevel_ >= D3D_FEATURE_LEVEL_9_3);
 
+	caps_.coordConvention = CoordConvention::Direct3D11;
+
 	// Seems like a fair approximation...
 	caps_.dualSourceBlend = featureLevel_ >= D3D_FEATURE_LEVEL_10_0;
 	caps_.depthClampSupported = featureLevel_ >= D3D_FEATURE_LEVEL_10_0;

Common/GPU/D3D9/thin3d_d3d9.cpp

@@ -717,6 +717,9 @@ D3D9Context::D3D9Context(IDirect3D9 *d3d, IDirect3D9Ex *d3dEx, int adapterId, ID
 	if (FAILED(d3d->GetAdapterIdentifier(adapterId, 0, &identifier_))) {
 		ERROR_LOG(Log::G3D,  "Failed to get adapter identifier: %d", adapterId);
 	}
+
+	caps_.coordConvention = CoordConvention::Direct3D9;
+
 	switch (identifier_.VendorId) {
 	case 0x10DE: caps_.vendor = GPUVendor::VENDOR_NVIDIA; break;
 	case 0x1002:

Common/GPU/MiscTypes.h

@@ -2,6 +2,9 @@
 
 #include "Common/Common.h"
 
+#include <functional>
+#include <cstdint>
+
 // Flags and structs shared between backends that haven't found a good home.
 
 enum class InvalidationFlags {
@@ -35,3 +38,11 @@ struct FrameTimeData {
 	double presentMargin;
 };
 constexpr size_t FRAME_TIME_HISTORY_LENGTH = 32;
+
+// Different APIs use different coordinate conventions
+enum class CoordConvention {
+	Direct3D9,
+	Direct3D11,
+	Vulkan,
+	OpenGL,
+};

Common/GPU/OpenGL/thin3d_gl.cpp

@@ -573,6 +573,7 @@ OpenGLContext::OpenGLContext(bool canChangeSwapInterval) : renderManager_(frameT
 		caps_.textureDepthSupported = true;
 	}
 
+	caps_.coordConvention = CoordConvention::OpenGL;
 	caps_.setMaxFrameLatencySupported = true;
 	caps_.dualSourceBlend = gl_extensions.ARB_blend_func_extended || gl_extensions.EXT_blend_func_extended;
 	caps_.anisoSupported = gl_extensions.EXT_texture_filter_anisotropic;

Common/GPU/Vulkan/thin3d_vulkan.cpp

@@ -880,6 +880,7 @@ VKContext::VKContext(VulkanContext *vulkan, bool useRenderThread)
 
 	INFO_LOG(Log::G3D, "Determining Vulkan device caps");
 
+	caps_.coordConvention = CoordConvention::Vulkan;
 	caps_.setMaxFrameLatencySupported = true;
 	caps_.anisoSupported = vulkan->GetDeviceFeatures().enabled.standard.samplerAnisotropy != 0;
 	caps_.geometryShaderSupported = vulkan->GetDeviceFeatures().enabled.standard.geometryShader != 0;

Common/GPU/thin3d.h

@@ -586,6 +586,7 @@ struct DeviceCaps {
 	GPUVendor vendor;
 	uint32_t deviceID;  // use caution!
 
+	CoordConvention coordConvention;
 	DataFormat preferredDepthBufferFormat;
 	DataFormat preferredShadowMapFormatLow;
 	DataFormat preferredShadowMapFormatHigh;

Common/System/Display.cpp

@@ -2,6 +2,7 @@
 
 #include "Common/System/Display.h"
 #include "Common/Math/math_util.h"
+#include "Common/GPU/MiscTypes.h"
 
 DisplayProperties g_display;
 
@@ -66,3 +67,35 @@ void DisplayProperties::Print() {
 	printf("rotation: %d\n", (int)rotation);
 	rot_matrix.print();
 }
+
+Lin::Matrix4x4 ComputeOrthoMatrix(float xres, float yres, CoordConvention coordConvention) {
+	using namespace Lin;
+	// TODO: Should be able to share the y-flip logic here with the one in postprocessing/presentation, for example.
+	Matrix4x4 ortho;
+	switch (coordConvention) {
+	case CoordConvention::Vulkan:
+		ortho.setOrthoD3D(0.0f, xres, 0, yres, -1.0f, 1.0f);
+		break;
+	case CoordConvention::Direct3D9:
+		ortho.setOrthoD3D(0.0f, xres, yres, 0.0f, -1.0f, 1.0f);
+		Matrix4x4 translation;
+		// Account for the small window adjustment.
+		translation.setTranslation(Vec3(
+			-0.5f * g_display.dpi_scale_x / g_display.dpi_scale_real_x,
+			-0.5f * g_display.dpi_scale_y / g_display.dpi_scale_real_y, 0.0f));
+		ortho = translation * ortho;
+		break;
+	case CoordConvention::Direct3D11:
+		ortho.setOrthoD3D(0.0f, xres, yres, 0.0f, -1.0f, 1.0f);
+		break;
+	case CoordConvention::OpenGL:
+	default:
+		ortho.setOrtho(0.0f, xres, yres, 0.0f, -1.0f, 1.0f);
+		break;
+	}
+	// Compensate for rotated display if needed.
+	if (g_display.rotation != DisplayRotation::ROTATE_0) {
+		ortho = ortho * g_display.rot_matrix;
+	}
+	return ortho;
+}

Common/System/Display.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "Common/Math/lin/matrix4x4.h"
+#include "Common/GPU/MiscTypes.h"
 
 // This is meant to be a framework for handling DPI scaling etc.
 // For now, it just consists of these ugly globals.
@@ -50,3 +51,5 @@ struct DisplayRect {
 
 void RotateRectToDisplay(DisplayRect<float> &rect, float rtWidth, float rtHeight);
 void RotateRectToDisplay(DisplayRect<int> &rect, int rtWidth, int rtHeight);
+
+Lin::Matrix4x4 ComputeOrthoMatrix(float xres, float yres, CoordConvention coordConvention);

UI/NativeApp.cpp

@@ -1016,38 +1016,6 @@ void CallbackPostRender(UIContext *dc, void *userdata) {
 	}
 }
 
-static Matrix4x4 ComputeOrthoMatrix(float xres, float yres) {
-	// TODO: Should be able to share the y-flip logic here with the one in postprocessing/presentation, for example.
-	Matrix4x4 ortho;
-	switch (GetGPUBackend()) {
-	case GPUBackend::VULKAN:
-		ortho.setOrthoD3D(0.0f, xres, 0, yres, -1.0f, 1.0f);
-		break;
-	case GPUBackend::DIRECT3D9:
-		ortho.setOrthoD3D(0.0f, xres, yres, 0.0f, -1.0f, 1.0f);
-		Matrix4x4 translation;
-		// Account for the small window adjustment.
-		translation.setTranslation(Vec3(
-			-0.5f * g_display.dpi_scale_x / g_display.dpi_scale_real_x,
-			-0.5f * g_display.dpi_scale_y / g_display.dpi_scale_real_y, 0.0f));
-		ortho = translation * ortho;
-		break;
-	case GPUBackend::DIRECT3D11:
-		ortho.setOrthoD3D(0.0f, xres, yres, 0.0f, -1.0f, 1.0f);
-		break;
-	case GPUBackend::OPENGL:
-	default:
-		ortho.setOrtho(0.0f, xres, yres, 0.0f, -1.0f, 1.0f);
-		break;
-	}
-
-	// Compensate for rotated display if needed.
-	if (g_display.rotation != DisplayRotation::ROTATE_0) {
-		ortho = ortho * g_display.rot_matrix;
-	}
-	return ortho;
-}
-
 static void SendMouseDeltaAxis();
 
 void NativeFrame(GraphicsContext *graphicsContext) {
@@ -1115,8 +1083,7 @@ void NativeFrame(GraphicsContext *graphicsContext) {
 	g_requestManager.ProcessRequests();
 
 	// Apply the UIContext bounds as a 2D transformation matrix.
-	// TODO: This should be moved into the draw context...
-	Matrix4x4 ortho = ComputeOrthoMatrix(g_display.dp_xres, g_display.dp_yres);
+	Matrix4x4 ortho = ComputeOrthoMatrix(g_display.dp_xres, g_display.dp_yres, graphicsContext->GetDrawContext()->GetDeviceCaps().coordConvention);
 
 	Draw::DebugFlags debugFlags = Draw::DebugFlags::NONE;
 	if ((DebugOverlay)g_Config.iDebugOverlay == DebugOverlay::GPU_PROFILE)