t/gui: Add SDL2 based GUI target

CMakeLists.txt

@@ -29,6 +29,7 @@ find_package(OpenHMD)
 find_package(OpenCV COMPONENTS core calib3d highgui imgproc imgcodecs features2d video)
 find_package(Libusb1)
 find_package(JPEG)
+find_package(SDL2)
 
 # @TODO Turn into a find_package LIBUVC file.
 pkg_check_modules(LIBUVC libuvc)
@@ -59,6 +60,7 @@ cmake_dependent_option(BUILD_WITH_LIBUVC "Enable libuvc video driver" ON "LIBUVC
 cmake_dependent_option(BUILD_WITH_FFMPEG "Enable ffmpeg testing video driver" ON "FFMPEG_FOUND" OFF)
 cmake_dependent_option(BUILD_WITH_HIDAPI "Enable HIDAPI-based driver(s) (OSVR HDK, PSVR)" ON "HIDAPI_FOUND" OFF)
 cmake_dependent_option(BUILD_WITH_OPENHMD "Enable OpenHMD driver" ON "OPENHMD_FOUND" OFF)
+cmake_dependent_option(BUILD_WITH_SDL2 "Enable SDL2 based test application" ON "SDL2_FOUND" OFF)
 
 
 ###
@@ -101,6 +103,18 @@ if(BUILD_WITH_FFMPEG)
 	add_definitions(-DXRT_HAVE_FFMPEG)
 endif()
 
+if(BUILD_WITH_SDL2)
+	add_definitions(-DXRT_HAVE_SDL2)
+
+	# Arch work around
+	if(NOT DEFINED SDL2_LIBRARIES)
+		set(SDL2_LIBRARIES SDL2::SDL2)
+	endif()
+
+	# SDL2 based gui
+	set(BUILD_TARGET_GUI TRUE)
+endif()
+
 if(BUILD_WITH_OPENHMD)
 	add_definitions(-DXRT_HAVE_OPENHMD)
 

src/xrt/targets/CMakeLists.txt

@@ -56,3 +56,7 @@ include_directories(${CMAKE_CURRENT_BINARY_DIR})
 add_subdirectory(common)
 add_subdirectory(openxr)
 add_subdirectory(cli)
+
+if(BUILD_TARGET_GUI)
+	add_subdirectory(gui)
+endif()

src/xrt/targets/gui/CMakeLists.txt

@@ -0,0 +1,62 @@
+# Copyright 2019, Collabora, Ltd.
+# SPDX-License-Identifier: BSL-1.0
+
+######
+# Create a small SDL2 based GUI for Monado.
+
+include_directories(
+	${CMAKE_CURRENT_SOURCE_DIR}/../../targets/common
+	${CMAKE_CURRENT_SOURCE_DIR}/../../auxiliary
+	${CMAKE_CURRENT_SOURCE_DIR}/../../include
+	${CMAKE_CURRENT_SOURCE_DIR}/../../drivers
+	${CMAKE_CURRENT_SOURCE_DIR}/../../../external
+	${SDL2_INCLUDE_DIRS}
+	)
+
+set(SOURCE_FILES
+	gui_common.h
+	gui_main.c
+	gui_sdl2.c
+	../../../external/glad/gl.h
+	../../../external/glad/gl.c
+	)
+
+add_executable(gui
+	${SOURCE_FILES}
+	$<TARGET_OBJECTS:aux_os>
+	$<TARGET_OBJECTS:aux_util>
+	$<TARGET_OBJECTS:aux_math>
+	$<TARGET_OBJECTS:st_prober>
+	$<TARGET_OBJECTS:target_lists>
+	)
+
+set_target_properties(gui PROPERTIES
+	OUTPUT_NAME monado-gui
+	PREFIX ""
+	)
+
+target_link_libraries(gui PRIVATE
+	${LIBUSB_LIBRARIES}
+	${LIBUVC_LIBRARIES}
+	${UDEV_LIBRARIES}
+	${SDL2_LIBRARIES}
+	)
+
+if(BUILD_TRACKING)
+	target_link_libraries(gui PRIVATE
+		$<TARGET_OBJECTS:aux_tracking>
+		${OpenCV_LIBRARIES}
+		)
+endif()
+
+if(DRIVER_OBJECTS)
+	target_sources(gui PRIVATE ${DRIVER_OBJECTS})
+endif()
+
+if(BUILD_WITH_JPEG)
+	target_link_libraries(gui PRIVATE ${JPEG_LIBRARIES})
+endif()
+
+if(DRIVER_LIBRARIES)
+	target_link_libraries(gui PRIVATE ${DRIVER_LIBRARIES})
+endif()

src/xrt/targets/gui/gui_common.h

@@ -0,0 +1,91 @@
+// Copyright 2019, Collabora, Ltd.
+// SPDX-License-Identifier: BSL-1.0
+/*!
+ * @file
+ * @brief  Common file for the Monado GUI program.
+ * @author Jakob Bornecrantz <jakob@collabora.com>
+ * @ingroup gui
+ */
+
+#pragma once
+
+#include "xrt/xrt_defines.h"
+#include <SDL2/SDL.h>
+
+/*!
+ * @defgroup gui GUI Config Interface
+ * @ingroup xrt
+ *
+ * @brief Small GUI interface to configure Monado based on SDL2.
+ */
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*!
+ * Common struct holding state for the GUI interface.
+ *
+ * @ingroup gui
+ */
+struct program
+{
+	SDL_Window *win;
+	SDL_GLContext ctx;
+
+	bool stopped;
+	bool initialized;
+
+	struct
+	{
+		SDL_Surface *sf;
+		uint8_t *buffer;
+		size_t stride;
+		uint32_t width;
+		uint32_t height;
+		bool own_buffer;
+	} blit;
+};
+
+/*!
+ * Init SDL2, create and show a window and bring up any other structs needed.
+ *
+ * @ingroup gui
+ */
+int
+gui_sdl2_init(struct program *p);
+
+/*!
+ * Loop until quit signal has been received.
+ *
+ * @ingroup gui
+ */
+void
+gui_sdl2_loop(struct program *p);
+
+/*!
+ * Display a 24bit RGB image on the screen.
+ *
+ * @ingroup gui
+ */
+void
+gui_sdl2_display_R8G8B8(struct program *p,
+                        bool resize,
+                        uint32_t width,
+                        uint32_t height,
+                        size_t stride,
+                        void *data);
+
+/*!
+ * Destroy all SDL things and quit SDL.
+ *
+ * @ingroup gui
+ */
+void
+gui_sdl2_quit(struct program *p);
+
+
+#ifdef __cplusplus
+}
+#endif

src/xrt/targets/gui/gui_main.c

@@ -0,0 +1,30 @@
+// Copyright 2019, Collabora, Ltd.
+// SPDX-License-Identifier: BSL-1.0
+/*!
+ * @file
+ * @brief  Main entrypoint for the Monado GUI program.
+ * @author Jakob Bornecrantz <jakob@collabora.com>
+ * @ingroup gui
+ */
+
+#include "gui_common.h"
+
+
+int
+main(int argc, char **argv)
+{
+	struct program p = {0};
+	int ret;
+
+	ret = gui_sdl2_init(&p);
+	if (ret != 0) {
+		gui_sdl2_quit(&p);
+		return ret;
+	}
+
+	gui_sdl2_loop(&p);
+
+	gui_sdl2_quit(&p);
+
+	return 0;
+}

src/xrt/targets/gui/gui_sdl2.c

@@ -0,0 +1,202 @@
+// Copyright 2019, Collabora, Ltd.
+// SPDX-License-Identifier: BSL-1.0
+/*!
+ * @file
+ * @brief  SDL2 functions to drive the GUI.
+ * @author Jakob Bornecrantz <jakob@collabora.com>
+ * @ingroup gui
+ */
+
+#include "gui_common.h"
+#include "glad/gl.h"
+
+
+/*
+ *
+ * Internal static functions
+ *
+ */
+
+XRT_MAYBE_UNUSED static void
+create_blit_info(struct program *p, uint32_t width, uint32_t height)
+{
+	if (p->blit.sf != NULL) {
+		SDL_FreeSurface(p->blit.sf);
+		p->blit.sf = NULL;
+
+		if (p->blit.own_buffer) {
+			free(p->blit.buffer);
+		}
+		p->blit.buffer = NULL;
+	}
+
+	size_t stride = width * 4;
+	size_t size = stride * height;
+	p->blit.width = width;
+	p->blit.height = height;
+	p->blit.stride = stride;
+	p->blit.own_buffer = true;
+
+	p->blit.buffer = malloc(size);
+	p->blit.sf =
+	    SDL_CreateRGBSurfaceFrom(p->blit.buffer, width, height, 32, stride,
+	                             0x0000FF, 0x00FF00, 0xFF0000, 0);
+}
+
+static void
+sdl2_handle_keydown(struct program *p, const SDL_Event *e)
+{
+	switch (e->key.keysym.sym) {
+	case SDLK_ESCAPE: p->stopped = true; break;
+	default: break;
+	}
+
+	return;
+}
+
+
+/*
+ *
+ * "Exported" functions.
+ *
+ */
+
+void
+gui_sdl2_display_R8G8B8(struct program *p,
+                        bool resize,
+                        uint32_t width,
+                        uint32_t height,
+                        size_t stride,
+                        void *data)
+{
+	if (p->blit.buffer != data || p->blit.width != width ||
+	    p->blit.height != height || p->blit.sf == NULL) {
+
+		if (resize) {
+			SDL_SetWindowSize(p->win, width, height);
+		}
+
+		p->blit.sf =
+		    SDL_CreateRGBSurfaceFrom(data, width, height, 24, stride,
+		                             0x0000FF, 0x00FF00, 0xFF0000, 0);
+
+		p->blit.width = width;
+		p->blit.height = height;
+		p->blit.stride = stride;
+		p->blit.buffer = data;
+		p->blit.own_buffer = false;
+	}
+
+	SDL_Surface *win_sf = SDL_GetWindowSurface(p->win);
+
+	if (SDL_BlitSurface(p->blit.sf, NULL, win_sf, NULL) == 0) {
+		SDL_UpdateWindowSurface(p->win);
+	}
+}
+
+void
+gui_sdl2_loop(struct program *p)
+{
+	SDL_Event event;
+	while (!p->stopped) {
+		if (SDL_WaitEvent(&event) == 0) {
+			return;
+		}
+
+		if (event.type == SDL_QUIT) {
+			return;
+		}
+
+		if (event.type == SDL_KEYDOWN) {
+			sdl2_handle_keydown(p, &event);
+		}
+	}
+
+	return;
+}
+
+int
+gui_sdl2_init(struct program *p)
+{
+	if (SDL_Init(SDL_INIT_EVERYTHING) < 0) {
+		return -1;
+	}
+
+	const char *title = "Monado! ☺";
+	int x = SDL_WINDOWPOS_UNDEFINED;
+	int y = SDL_WINDOWPOS_UNDEFINED;
+	int w = 1920;
+	int h = 1080;
+
+	SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, 0);
+	SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK,
+	                    SDL_GL_CONTEXT_PROFILE_CORE);
+	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
+	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
+	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
+	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
+	SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
+
+	SDL_WindowFlags window_flags = 0;
+	window_flags |= SDL_WINDOW_SHOWN;
+	window_flags |= SDL_WINDOW_OPENGL;
+	window_flags |= SDL_WINDOW_RESIZABLE;
+	window_flags |= SDL_WINDOW_ALLOW_HIGHDPI;
+#if 0
+	window_flags |= SDL_WINDOW_MAXIMIZED;
+#endif
+
+	p->initialized = true;
+	p->win = SDL_CreateWindow(title, x, y, w, h, window_flags);
+
+	if (p->win == NULL) {
+		return -1;
+	}
+
+	p->ctx = SDL_GL_CreateContext(p->win);
+	if (p->ctx == NULL) {
+		return -1;
+	}
+
+	SDL_GL_MakeCurrent(p->win, p->ctx);
+	SDL_GL_SetSwapInterval(1); // Enable vsync
+
+	// Setup OpenGL bindings.
+	bool err = gladLoadGL((GLADloadfunc)SDL_GL_GetProcAddress) == 0;
+	if (err) {
+		return -1;
+	}
+
+	return 0;
+}
+
+void
+gui_sdl2_quit(struct program *p)
+{
+	if (!p->initialized) {
+		return;
+	}
+
+	if (p->blit.sf != NULL) {
+		SDL_FreeSurface(p->blit.sf);
+		p->blit.sf = NULL;
+
+		if (p->blit.own_buffer) {
+			free(p->blit.buffer);
+		}
+		p->blit.buffer = NULL;
+	}
+
+	if (p->ctx != NULL) {
+		SDL_GL_DeleteContext(p->ctx);
+		p->ctx = NULL;
+	}
+
+	if (p->win != NULL) {
+		SDL_DestroyWindow(p->win);
+		p->win = NULL;
+	}
+
+	SDL_Quit();
+	p->initialized = false;
+}