DX12: added macro DISABLE_DX12 that allows to disable DX12 backend.

src/engine/platform/win_glimp.c

@@ -414,11 +414,11 @@ static HWND create_main_window(int width, int height, qboolean fullscreen)
 		strcpy(window_name, MAIN_WINDOW_CLASS_NAME);
 	} else {
 		const char* api_name = "invalid-render-api";
-		if (r_renderAPI->integer == 0)
+		if (get_render_api() == RENDER_API_GL)
 			api_name = "OpenGL";
-		else if (r_renderAPI->integer == 1)
+		else if (get_render_api() == RENDER_API_VK)
 			api_name = "Vulkan";
-		else if (r_renderAPI->integer == 2)
+		else if (get_render_api() == RENDER_API_DX)
 			api_name = "DX12";
 		sprintf(window_name, "%s [%s]", MAIN_WINDOW_CLASS_NAME, api_name);
 	}
@@ -445,7 +445,7 @@ static HWND create_main_window(int width, int height, qboolean fullscreen)
     return hwnd;
 }
 
-static HWND create_twin_window(int width, int height, int render_api)
+static HWND create_twin_window(int width, int height, RenderApi render_api)
 {
     //
     // register the window class if necessary
@@ -494,15 +494,15 @@ static HWND create_twin_window(int width, int height, int render_api)
     cvar_t* vid_ypos = ri.Cvar_Get ("vid_ypos", "", 0);
 	int x, y;
 
-	bool show_three_windows = (r_twinMode->integer | (1 << r_renderAPI->integer)) == 7;
+	bool show_three_windows = (r_twinMode->integer | (1 << get_render_api())) == 7;
 
 	if (!show_three_windows) { // two windows
 		x = vid_xpos->integer + width + 5; // offset to the right of the main window
 		y = vid_ypos->integer;
 	} else { // three windows
 		bool first_twin_window =
-			(r_renderAPI->integer > 0 && render_api == 0) ||
+			(get_render_api() != RENDER_API_GL && render_api == RENDER_API_GL) ||
-			(r_renderAPI->integer == 0 && render_api == 1);
+			(get_render_api() == RENDER_API_GL && render_api == RENDER_API_VK);
 
 		if (first_twin_window) {
 			x = vid_xpos->integer + width + 5;
@@ -529,11 +529,11 @@ static HWND create_twin_window(int width, int height, int render_api)
 	
 	char window_name[1024];
 	const char* api_name = "invalid-render-api";
-	if (render_api == 0)
+	if (render_api == RENDER_API_GL)
 		api_name = "OpenGL";
-	else if (render_api == 1)
+	else if (render_api == RENDER_API_VK)
 		api_name = "Vulkan";
-	else if (render_api == 2)
+	else if (render_api == RENDER_API_DX)
 		api_name = "DX12";
 	sprintf(window_name, "%s [%s]", MAIN_WINDOW_CLASS_NAME, api_name);
 
@@ -752,14 +752,14 @@ void GLimp_Init( void )
 
 	SetMode(r_mode->integer, (qboolean)r_fullscreen->integer);
 
-	if (r_renderAPI->integer == 0) {
+	if (get_render_api() == RENDER_API_GL) {
 		g_wv.hWnd_opengl = create_main_window(glConfig.vidWidth, glConfig.vidHeight, (qboolean)r_fullscreen->integer);
 		g_wv.hWnd = g_wv.hWnd_opengl;
 		SetForegroundWindow(g_wv.hWnd);
 		SetFocus(g_wv.hWnd);
 		WG_CheckHardwareGamma();
 	} else {
-		g_wv.hWnd_opengl = create_twin_window(glConfig.vidWidth, glConfig.vidHeight, 0);
+		g_wv.hWnd_opengl = create_twin_window(glConfig.vidWidth, glConfig.vidHeight, RENDER_API_GL);
 	}
 
 	if (!GLW_InitDriver(g_wv.hWnd_opengl)) {
@@ -864,14 +864,14 @@ void vk_imp_init() {
 	// Create window.
 	SetMode(r_mode->integer, (qboolean)r_fullscreen->integer);
 
-	if (r_renderAPI->integer == 1) {
+	if (get_render_api() == RENDER_API_VK) {
 		g_wv.hWnd_vulkan = create_main_window(glConfig.vidWidth, glConfig.vidHeight, (qboolean)r_fullscreen->integer);
 		g_wv.hWnd = g_wv.hWnd_vulkan;
 		SetForegroundWindow(g_wv.hWnd);
 		SetFocus(g_wv.hWnd);
 		WG_CheckHardwareGamma();
 	} else {
-		g_wv.hWnd_vulkan = create_twin_window(glConfig.vidWidth, glConfig.vidHeight, 1);
+		g_wv.hWnd_vulkan = create_twin_window(glConfig.vidWidth, glConfig.vidHeight, RENDER_API_VK);
 	}
 }
 
@@ -933,14 +933,14 @@ void dx_imp_init() {
 	// Create window.
 	SetMode(r_mode->integer, (qboolean)r_fullscreen->integer);
 
-	if (r_renderAPI->integer == 2) {
+	if (get_render_api() == RENDER_API_DX) {
 		g_wv.hWnd_dx = create_main_window(glConfig.vidWidth, glConfig.vidHeight, (qboolean)r_fullscreen->integer);
 		g_wv.hWnd = g_wv.hWnd_dx;
 		SetForegroundWindow(g_wv.hWnd);
 		SetFocus(g_wv.hWnd);
 		WG_CheckHardwareGamma();
 	} else {
-		g_wv.hWnd_dx = create_twin_window(glConfig.vidWidth, glConfig.vidHeight, 2);
+		g_wv.hWnd_dx = create_twin_window(glConfig.vidWidth, glConfig.vidHeight, RENDER_API_DX);
 	}
 }
 

src/engine/renderer/dx.cpp

@@ -4,9 +4,14 @@
 #include <chrono>
 #include <functional>
 
+#ifndef DISABLE_DX12
+
 #include "D3d12.h"
 #include "DXGI1_4.h"
 
+#pragma comment (lib, "D3d12.lib")
+#pragma comment (lib, "DXGI.lib")
+
 const int VERTEX_CHUNK_SIZE = 512 * 1024;
 
 const int XYZ_SIZE      = 4 * VERTEX_CHUNK_SIZE;
@@ -1479,3 +1484,23 @@ void dx_end_frame() {
 
 	DX_CHECK(dx.swapchain->Present(0, 0));
 }
+
+#else // DISABLE_DX12
+
+void dx_initialize() {}
+void dx_shutdown() {}
+void dx_release_resources() {}
+void dx_wait_device_idle() {}
+
+Dx_Image dx_create_image(int width, int height, Dx_Image_Format format, int mip_levels,  bool repeat_texture, int image_index) { return Dx_Image{}; }
+void dx_upload_image_data(ID3D12Resource* texture, int width, int height, int mip_levels, const uint8_t* pixels, int bytes_per_pixel) {}
+void dx_create_sampler_descriptor(const Vk_Sampler_Def& def, Dx_Sampler_Index sampler_index) {}
+ID3D12PipelineState* dx_find_pipeline(const Vk_Pipeline_Def& def) { return nullptr; }
+
+void dx_clear_attachments(bool clear_depth_stencil, bool clear_color, vec4_t color) {}
+void dx_bind_geometry() {}
+void dx_shade_geometry(ID3D12PipelineState* pipeline, bool multitexture, Vk_Depth_Range depth_range, bool indexed, bool lines) {}
+void dx_begin_frame() {}
+void dx_end_frame() {}
+
+#endif  // DISABLE_DX12

src/engine/renderer/dx.h

@@ -1,5 +1,8 @@
 #pragma once
 
+// Uncomment the following line to disable DX12 backend
+//#define DISABLE_DX12
+
 struct ID3D12CommandAllocator;
 struct ID3D12GraphicsCommandList;
 struct ID3D12CommandQueue;

src/engine/renderer/tr_init.c

@@ -171,6 +171,20 @@ static void AssertCvarRange( cvar_t *cv, float minVal, float maxVal, qboolean sh
 	}
 }
 
+RenderApi get_render_api() {
+	if (r_renderAPI->integer == 0)
+		return RENDER_API_GL;
+	else if (r_renderAPI->integer == 1)
+		return RENDER_API_VK;
+	else if (r_renderAPI->integer == 2)
+#ifndef DISABLE_DX12
+		return RENDER_API_DX;
+#else
+		return RENDER_API_GL; // use default (GL) if dx12 is disabled
+#endif
+	else
+		return RENDER_API_GL; // use default (GL) if invalid r_renderAPI value is specified
+}
 
 /*
 ** This function is responsible for initializing a valid OpenGL/Vulkan subsystem.
@@ -190,8 +204,14 @@ static void InitRenderAPI( void )
 	//
 	if ( glConfig.vidWidth == 0 )
 	{
+#ifdef DISABLE_DX12
+		if (r_renderAPI->integer == 2) {
+			ri.Printf(PRINT_WARNING, "DirectX 12 backend is disabled (code was compiled with DISABLE_DX12). OpenGL backend will be used instead.\n");
+		}
+#endif
+
 		// OpenGL
-		if (r_renderAPI->integer == 0 || (r_twinMode->integer&1)) {
+		if (get_render_api() == RENDER_API_GL || (r_twinMode->integer&1)) {
 			GLimp_Init();
 
 			GLint temp;
@@ -202,16 +222,18 @@ static void InitRenderAPI( void )
 		}
 
 		// VULKAN
-		if (r_renderAPI->integer == 1 || (r_twinMode->integer&2)) {
+		if (get_render_api() == RENDER_API_VK || (r_twinMode->integer&2)) {
 			vk_imp_init();
 			vk_initialize();
 		}
 
 		// DX12
-		if (r_renderAPI->integer == 2 || (r_twinMode->integer&4)) {
+#ifndef DISABLE_DX12
+		if (get_render_api() == RENDER_API_DX || (r_twinMode->integer&4)) {
 			dx_imp_init();
 			dx_initialize();
 		}
+#endif
 	}
 
 	// init command buffers and SMP
@@ -375,9 +397,9 @@ void RB_TakeScreenshot( int x, int y, int width, int height, char *fileName ) {
 	buffer[15] = height >> 8;
 	buffer[16] = 24;	// pixel size
 
-	if (r_renderAPI->integer == 0) {
+	if (get_render_api() == RENDER_API_GL) {
 		qglReadPixels( x, y, width, height, GL_RGB, GL_UNSIGNED_BYTE, buffer+18 ); 
-	} else if (r_renderAPI->integer == 1) { // VULKAN
+	} else if (get_render_api() == RENDER_API_VK) { // VULKAN
 		byte* buffer2 = (byte*) ri.Hunk_AllocateTempMemory(glConfig.vidWidth*glConfig.vidHeight*4);
 
 		vk_read_pixels(buffer2);
@@ -392,7 +414,7 @@ void RB_TakeScreenshot( int x, int y, int width, int height, char *fileName ) {
 			buffer2_ptr += 4;
 		}
 		ri.Hunk_FreeTempMemory(buffer2);
-	} else if (r_renderAPI->integer == 2) { // DX12
+	} else if (get_render_api() == RENDER_API_DX) { // DX12
 		ri.Printf(PRINT_WARNING, "RT_TakeScreenshot is not implemented for DX12");
 	}
 
@@ -422,11 +444,11 @@ RB_TakeScreenshotJPEG
 void RB_TakeScreenshotJPEG( int x, int y, int width, int height, char *fileName ) {
 	byte* buffer = (byte*) ri.Hunk_AllocateTempMemory(glConfig.vidWidth*glConfig.vidHeight*4);;
 
-	if (r_renderAPI->integer == 0) {
+	if (get_render_api() == RENDER_API_GL) {
 		qglReadPixels( x, y, width, height, GL_RGBA, GL_UNSIGNED_BYTE, buffer ); 
-	} else if (r_renderAPI->integer == 1) { // VULKAN
+	} else if (get_render_api() == RENDER_API_VK) { // VULKAN
 		vk_read_pixels(buffer);
-	} else if (r_renderAPI->integer == 2) { // DX12
+	} else if (get_render_api() == RENDER_API_DX) { // DX12
 		ri.Printf(PRINT_WARNING, "RT_TakeScreenshotJPEG is not implemented for DX12");
 	}
 
@@ -562,9 +584,9 @@ void R_LevelShot( void ) {
 	buffer[14] = 128;
 	buffer[16] = 24;	// pixel size
 
-	if (r_renderAPI->integer == 0) {
+	if (get_render_api() == RENDER_API_GL) {
 		qglReadPixels( 0, 0, glConfig.vidWidth, glConfig.vidHeight, GL_RGB, GL_UNSIGNED_BYTE, source ); 
-	} else if (r_renderAPI->integer == 1) { // VULKAN
+	} else if (get_render_api() == RENDER_API_VK) { // VULKAN
 		byte* buffer2 = (byte*) ri.Hunk_AllocateTempMemory(glConfig.vidWidth*glConfig.vidHeight*4);
 		vk_read_pixels(buffer2);
 
@@ -578,7 +600,7 @@ void R_LevelShot( void ) {
 			buffer2_ptr += 4;
 		}
 		ri.Hunk_FreeTempMemory(buffer2);
-	} else if (r_renderAPI->integer == 2) { // DX12
+	} else if (get_render_api() == RENDER_API_DX) { // DX12
 		ri.Printf(PRINT_WARNING, "R_LevelShot is not implemented for DX12");
 	}
 

src/engine/renderer/tr_local.h

@@ -945,6 +945,13 @@ extern Vk_World		vk_world;		// this data is cleared during ref re-init
 extern Dx_Instance	dx;				// shouldn't be cleared during ref re-init
 extern Dx_World		dx_world;		// this data is cleared during ref re-init
 
+enum RenderApi {
+	RENDER_API_GL,
+	RENDER_API_VK,
+	RENDER_API_DX
+};
+
+RenderApi get_render_api();
 
 //
 // cvars

visual-studio/quake3.vcxproj

@@ -79,7 +79,7 @@
       <Culture>0x0409</Culture>
     </ResourceCompile>
     <Link>
-      <AdditionalDependencies>winmm.lib;wsock32.lib;D3d12.lib;DXGI.lib;d3dcompiler.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <AdditionalDependencies>winmm.lib;wsock32.lib;%(AdditionalDependencies)</AdditionalDependencies>
       <SuppressStartupBanner>true</SuppressStartupBanner>
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <SubSystem>Windows</SubSystem>
@@ -120,7 +120,7 @@
       <Culture>0x0409</Culture>
     </ResourceCompile>
     <Link>
-      <AdditionalDependencies>winmm.lib;wsock32.lib;D3d12.lib;DXGI.lib;d3dcompiler.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <AdditionalDependencies>winmm.lib;wsock32.lib;%(AdditionalDependencies)</AdditionalDependencies>
       <SuppressStartupBanner>true</SuppressStartupBanner>
       <SubSystem>Windows</SubSystem>
       <StackReserveSize>8388608</StackReserveSize>