Added sdl3 and opengl 3 demo

demo/sdl3_opengl3/Makefile

@@ -0,0 +1,25 @@
+# Install
+BIN = demo
+
+# Flags
+CFLAGS += -g -std=c89 -Wall -Wextra -pedantic -DSDL_DISABLE_IMMINTRIN_H
+
+SRC = main.c
+OBJ = $(SRC:.c=.o)
+
+ifeq ($(OS),Windows_NT)
+BIN := $(BIN).exe
+LIBS = -lmingw32 -lSDL3main -lSDL3 -lopengl32 -lm -lGLU32 -lGLEW32
+else
+	UNAME_S := $(shell uname -s)
+	ifeq ($(UNAME_S),Darwin)
+		LIBS = -lSDL3 -framework OpenGL -lm -lGLEW
+	else
+		LIBS = -lSDL3 -lGL -lm -lGLU -lGLEW
+	endif
+endif
+
+$(BIN):
+	@mkdir -p bin
+	rm -f bin/$(BIN) $(OBJS)
+	$(CC) $(SRC) $(CFLAGS) -o bin/$(BIN) $(LIBS)

demo/sdl3_opengl3/main.c

@@ -0,0 +1,237 @@
+/* nuklear - 1.32.0 - public domain */
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdarg.h>
+#include <string.h>
+#include <math.h>
+#include <assert.h>
+#include <limits.h>
+#include <time.h>
+
+#include <GL/glew.h>
+#include <SDL3/SDL.h>
+#include <SDL3/SDL_opengl.h>
+
+#define NK_INCLUDE_FIXED_TYPES
+#define NK_INCLUDE_STANDARD_IO
+#define NK_INCLUDE_STANDARD_VARARGS
+#define NK_INCLUDE_DEFAULT_ALLOCATOR
+#define NK_INCLUDE_VERTEX_BUFFER_OUTPUT
+#define NK_INCLUDE_FONT_BAKING
+#define NK_INCLUDE_DEFAULT_FONT
+#define NK_IMPLEMENTATION
+#define NK_SDL3_GL3_IMPLEMENTATION
+#include "../../nuklear.h"
+#include "nuklear_sdl3_gl3.h"
+
+#define WINDOW_WIDTH 1200
+#define WINDOW_HEIGHT 800
+
+#define MAX_VERTEX_MEMORY 512 * 1024
+#define MAX_ELEMENT_MEMORY 128 * 1024
+
+/* ===============================================================
+ *
+ *                          EXAMPLE
+ *
+ * ===============================================================*/
+/* This are some code examples to provide a small overview of what can be
+ * done with this library. To try out an example uncomment the defines */
+/*#define INCLUDE_ALL */
+/*#define INCLUDE_STYLE */
+/*#define INCLUDE_CALCULATOR */
+/*#define INCLUDE_CANVAS */
+#define INCLUDE_OVERVIEW
+/*#define INCLUDE_CONFIGURATOR */
+/*#define INCLUDE_NODE_EDITOR */
+
+#ifdef INCLUDE_ALL
+  #define INCLUDE_STYLE
+  #define INCLUDE_CALCULATOR
+  #define INCLUDE_CANVAS
+  #define INCLUDE_OVERVIEW
+  #define INCLUDE_CONFIGURATOR
+  #define INCLUDE_NODE_EDITOR
+#endif
+
+#ifdef INCLUDE_STYLE
+  #include "../../demo/common/style.c"
+#endif
+#ifdef INCLUDE_CALCULATOR
+  #include "../../demo/common/calculator.c"
+#endif
+#ifdef INCLUDE_CANVAS
+  #include "../../demo/common/canvas.c"
+#endif
+#ifdef INCLUDE_OVERVIEW
+  #include "../../demo/common/overview.c"
+#endif
+#ifdef INCLUDE_CONFIGURATOR
+  #include "../../demo/common/style_configurator.c"
+#endif
+#ifdef INCLUDE_NODE_EDITOR
+  #include "../../demo/common/node_editor.c"
+#endif
+
+/* ===============================================================
+ *
+ *                          DEMO
+ *
+ * ===============================================================*/
+int main(int argc, char *argv[])
+{
+    /* Platform */
+    SDL_Window *win;
+    SDL_GLContext glContext;
+    int win_width, win_height;
+    int running = 1;
+
+    /* GUI */
+    struct nk_context *ctx;
+    struct nk_colorf bg;
+
+    #ifdef INCLUDE_CONFIGURATOR
+    static struct nk_color color_table[NK_COLOR_COUNT];
+    memcpy(color_table, nk_default_color_style, sizeof(color_table));
+    #endif
+
+    NK_UNUSED(argc);
+    NK_UNUSED(argv);
+
+    /* SDL setup */
+    SDL_Init(SDL_INIT_VIDEO|SDL_INIT_EVENTS);
+    SDL_GL_SetAttribute (SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_FORWARD_COMPATIBLE_FLAG);
+    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, 3);
+    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
+    win = SDL_CreateWindow("sdl3_opengl3",
+        WINDOW_WIDTH, WINDOW_HEIGHT, SDL_WINDOW_OPENGL);
+    glContext = SDL_GL_CreateContext(win);
+    SDL_GetWindowSize(win, &win_width, &win_height);
+
+    /* OpenGL setup */
+    glViewport(0, 0, WINDOW_WIDTH, WINDOW_HEIGHT);
+    glewExperimental = 1;
+    if (glewInit() != GLEW_OK) {
+        fprintf(stderr, "Failed to setup GLEW\n");
+        exit(1);
+    }
+
+    ctx = nk_sdl_init(win);
+    /* Load Fonts: if none of these are loaded a default font will be used  */
+    /* Load Cursor: if you uncomment cursor loading please hide the cursor */
+    {struct nk_font_atlas *atlas;
+    nk_sdl_font_stash_begin(&atlas);
+    /*struct nk_font *droid = nk_font_atlas_add_from_file(atlas, "../../../extra_font/DroidSans.ttf", 14, 0);*/
+    /*struct nk_font *roboto = nk_font_atlas_add_from_file(atlas, "../../../extra_font/Roboto-Regular.ttf", 16, 0);*/
+    /*struct nk_font *future = nk_font_atlas_add_from_file(atlas, "../../../extra_font/kenvector_future_thin.ttf", 13, 0);*/
+    /*struct nk_font *clean = nk_font_atlas_add_from_file(atlas, "../../../extra_font/ProggyClean.ttf", 12, 0);*/
+    /*struct nk_font *tiny = nk_font_atlas_add_from_file(atlas, "../../../extra_font/ProggyTiny.ttf", 10, 0);*/
+    /*struct nk_font *cousine = nk_font_atlas_add_from_file(atlas, "../../../extra_font/Cousine-Regular.ttf", 13, 0);*/
+    nk_sdl_font_stash_end();
+    /*nk_style_load_all_cursors(ctx, atlas->cursors);*/
+    /*nk_style_set_font(ctx, &roboto->handle);*/}
+
+    /* style.c */
+    #ifdef INCLUDE_STYLE
+    /* ease regression testing during Nuklear release process; not needed for anything else */
+    #ifdef STYLE_WHITE
+    set_style(ctx, THEME_WHITE);
+    #elif defined(STYLE_RED)
+    set_style(ctx, THEME_RED);
+    #elif defined(STYLE_BLUE)
+    set_style(ctx, THEME_BLUE);
+    #elif defined(STYLE_DARK)
+    set_style(ctx, THEME_DARK);
+    #endif
+    #endif
+
+    bg.r = 0.10f, bg.g = 0.18f, bg.b = 0.24f, bg.a = 1.0f;
+    while (running)
+    {
+        /* Input */
+        SDL_Event evt;
+        nk_input_begin(ctx);
+        while (SDL_PollEvent(&evt)) {
+            if (evt.type == SDL_EVENT_QUIT) goto cleanup;
+            if (evt.type == SDL_EVENT_KEY_DOWN && evt.key.key == SDLK_Q && SDL_GetModState() & SDL_KMOD_CTRL) goto cleanup;
+            nk_sdl_handle_event(&evt);
+        }
+        nk_sdl_handle_grab(); /* optional grabbing behavior */
+        nk_input_end(ctx);
+
+        /* GUI */
+        if (nk_begin(ctx, "Demo", nk_rect(50, 50, 230, 250),
+            NK_WINDOW_BORDER|NK_WINDOW_MOVABLE|NK_WINDOW_SCALABLE|
+            NK_WINDOW_MINIMIZABLE|NK_WINDOW_TITLE))
+        {
+            enum {EASY, HARD};
+            static int op = EASY;
+            static int property = 20;
+
+            nk_layout_row_static(ctx, 30, 80, 1);
+            if (nk_button_label(ctx, "button"))
+                printf("button pressed!\n");
+            nk_layout_row_dynamic(ctx, 30, 2);
+            if (nk_option_label(ctx, "easy", op == EASY)) op = EASY;
+            if (nk_option_label(ctx, "hard", op == HARD)) op = HARD;
+            nk_layout_row_dynamic(ctx, 22, 1);
+            nk_property_int(ctx, "Compression:", 0, &property, 100, 10, 1);
+
+            nk_layout_row_dynamic(ctx, 20, 1);
+            nk_label(ctx, "background:", NK_TEXT_LEFT);
+            nk_layout_row_dynamic(ctx, 25, 1);
+            if (nk_combo_begin_color(ctx, nk_rgb_cf(bg), nk_vec2(nk_widget_width(ctx),400))) {
+                nk_layout_row_dynamic(ctx, 120, 1);
+                bg = nk_color_picker(ctx, bg, NK_RGBA);
+                nk_layout_row_dynamic(ctx, 25, 1);
+                bg.r = nk_propertyf(ctx, "#R:", 0, bg.r, 1.0f, 0.01f,0.005f);
+                bg.g = nk_propertyf(ctx, "#G:", 0, bg.g, 1.0f, 0.01f,0.005f);
+                bg.b = nk_propertyf(ctx, "#B:", 0, bg.b, 1.0f, 0.01f,0.005f);
+                bg.a = nk_propertyf(ctx, "#A:", 0, bg.a, 1.0f, 0.01f,0.005f);
+                nk_combo_end(ctx);
+            }
+        }
+        nk_end(ctx);
+
+        /* -------------- EXAMPLES ---------------- */
+        #ifdef INCLUDE_CALCULATOR
+          calculator(ctx);
+        #endif
+        #ifdef INCLUDE_CANVAS
+          canvas(ctx);
+        #endif
+        #ifdef INCLUDE_OVERVIEW
+          overview(ctx);
+        #endif
+        #ifdef INCLUDE_CONFIGURATOR
+          style_configurator(ctx, color_table);
+        #endif
+        #ifdef INCLUDE_NODE_EDITOR
+          node_editor(ctx);
+        #endif
+        /* ----------------------------------------- */
+
+        /* Draw */
+        SDL_GetWindowSize(win, &win_width, &win_height);
+        glViewport(0, 0, win_width, win_height);
+        glClear(GL_COLOR_BUFFER_BIT);
+        glClearColor(bg.r, bg.g, bg.b, bg.a);
+        /* IMPORTANT: `nk_sdl_render` modifies some global OpenGL state
+         * with blending, scissor, face culling, depth test and viewport and
+         * defaults everything back into a default state.
+         * Make sure to either a.) save and restore or b.) reset your own state after
+         * rendering the UI. */
+        nk_sdl_render(NK_ANTI_ALIASING_ON, MAX_VERTEX_MEMORY, MAX_ELEMENT_MEMORY);
+        SDL_GL_SwapWindow(win);
+    }
+
+cleanup:
+    nk_sdl_shutdown();
+    SDL_GL_DestroyContext(glContext);
+    SDL_DestroyWindow(win);
+    SDL_Quit();
+    return 0;
+}