Add examples

examples/game.odin

@@ -0,0 +1,221 @@
+import win32 "sys/windows.odin" when ODIN_OS == "windows";
+import wgl "sys/wgl.odin" when ODIN_OS == "windows";
+import "fmt.odin";
+import "math.odin";
+import "os.odin";
+import gl "opengl.odin";
+
+TWO_HEARTS :: '💕';
+
+win32_perf_count_freq := win32.get_query_performance_frequency();
+time_now :: proc() -> f64 {
+	assert(win32_perf_count_freq != 0);
+
+	counter: i64;
+	win32.query_performance_counter(&counter);
+	return f64(counter) / f64(win32_perf_count_freq);
+}
+win32_print_last_error :: proc() {
+	err_code := win32.get_last_error();
+	if err_code != 0 {
+		fmt.println("get_last_error: ", err_code);
+	}
+}
+
+// Yuk!
+to_c_string :: proc(s: string) -> []u8 {
+	c_str := make([]u8, len(s)+1);
+	copy(c_str, cast([]u8)s);
+	c_str[len(s)] = 0;
+	return c_str;
+}
+
+
+Window :: struct {
+	width, height:      int;
+	wc:                 win32.Wnd_Class_Ex_A;
+	dc:                 win32.Hdc;
+	hwnd:               win32.Hwnd;
+	opengl_context, rc: wgl.Hglrc;
+	c_title:            []u8;
+}
+
+make_window :: proc(title: string, msg, height: int, window_proc: win32.Wnd_Proc) -> (Window, bool) {
+	using win32;
+
+	w: Window;
+	w.width, w.height = msg, height;
+
+	class_name := "Win32-Odin-Window\x00";
+	c_class_name := &class_name[0];
+	if title[len(title)-1] != 0 {
+		w.c_title = to_c_string(title);
+	} else {
+		w.c_title = cast([]u8)title;
+	}
+
+	instance := get_module_handle_a(nil);
+
+	w.wc = Wnd_Class_Ex_A{
+		size       = size_of(Wnd_Class_Ex_A),
+		style      = CS_VREDRAW | CS_HREDRAW,
+		instance   = Hinstance(instance),
+		class_name = c_class_name,
+		wnd_proc   = window_proc,
+	};
+
+	if register_class_ex_a(&w.wc) == 0 {
+		win32_print_last_error();
+		return w, false;
+	}
+
+	w.hwnd = create_window_ex_a(0,
+	                            c_class_name, &w.c_title[0],
+	                            WS_VISIBLE | WS_OVERLAPPED | WS_CAPTION | WS_SYSMENU | WS_MINIMIZEBOX,
+	                            CW_USEDEFAULT, CW_USEDEFAULT,
+	                            i32(w.width), i32(w.height),
+	                            nil, nil, instance, nil);
+
+	if w.hwnd == nil {
+		win32_print_last_error();
+		return w, false;
+	}
+
+	w.dc = get_dc(w.hwnd);
+
+	{
+		pfd := Pixel_Format_Descriptor{
+			size         = size_of(Pixel_Format_Descriptor),
+			version      = 1,
+			flags        = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER,
+			pixel_type   = PFD_TYPE_RGBA,
+			color_bits   = 32,
+			alpha_bits   = 8,
+			depth_bits   = 24,
+			stencil_bits = 8,
+			layer_type   = PFD_MAIN_PLANE,
+		};
+
+		set_pixel_format(w.dc, choose_pixel_format(w.dc, &pfd), nil);
+		w.opengl_context = wgl.create_context(w.dc);
+		wgl.make_current(w.dc, w.opengl_context);
+
+		attribs := [8]i32{
+			wgl.CONTEXT_MAJOR_VERSION_ARB, 2,
+			wgl.CONTEXT_MINOR_VERSION_ARB, 1,
+			wgl.CONTEXT_PROFILE_MASK_ARB, wgl.CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB,
+			0, // NOTE(bill): tells the that :: proc this is the end of attribs
+		};
+
+		wgl_str := "wglCreateContextAttribsARB\x00";
+		wglCreateContextAttribsARB := cast(wgl.Create_Context_Attribs_ARB_Type)wgl.get_proc_address(&wgl_str[0]);
+		w.rc = wglCreateContextAttribsARB(w.dc, nil, &attribs[0]);
+		wgl.make_current(w.dc, w.rc);
+		swap_buffers(w.dc);
+	}
+
+	return w, true;
+}
+
+destroy_window :: proc(w: ^Window) {
+	free(w.c_title);
+}
+
+display_window :: proc(w: ^Window) {
+	win32.swap_buffers(w.dc);
+}
+
+
+run :: proc() {
+	using math;
+
+	win32_proc :: proc(hwnd: win32.Hwnd, msg: u32, wparam: win32.Wparam, lparam: win32.Lparam) -> win32.Lresult #no_inline {
+		using win32;
+		if msg == WM_DESTROY || msg == WM_CLOSE || msg == WM_QUIT {
+			os.exit(0);
+			return 0;
+		}
+		return def_window_proc_a(hwnd, msg, wparam, lparam);
+	}
+
+	window, window_success := make_window("Odin Language Demo", 854, 480, cast(win32.Wnd_Proc)win32_proc);
+	if !window_success {
+		return;
+	}
+	defer destroy_window(&window);
+
+	gl.init();
+
+	using win32;
+
+	prev_time := time_now();
+	running := true;
+
+	pos := Vec2{100, 100};
+
+	for running {
+		curr_time := time_now();
+		dt := f32(curr_time - prev_time);
+		prev_time = curr_time;
+
+		msg: Msg;
+		for peek_message_a(&msg, nil, 0, 0, PM_REMOVE) > 0 {
+			if msg.message == WM_QUIT {
+				running = false;
+			}
+			translate_message(&msg);
+			dispatch_message_a(&msg);
+		}
+
+		if is_key_down(Key_Code.Escape) {
+			running = false;
+		}
+
+		{
+			SPEED :: 500;
+			v: Vec2;
+
+			if is_key_down(Key_Code.Right) do v[0] += 1;
+			if is_key_down(Key_Code.Left)  do v[0] -= 1;
+			if is_key_down(Key_Code.Up)    do v[1] += 1;
+			if is_key_down(Key_Code.Down)  do v[1] -= 1;
+
+			v = norm(v);
+
+			pos += v * Vec2{SPEED * dt};
+		}
+
+
+		gl.ClearColor(0.5, 0.7, 1.0, 1.0);
+		gl.Clear(gl.COLOR_BUFFER_BIT);
+
+		gl.LoadIdentity();
+		gl.Ortho(0, f64(window.width),
+		         0, f64(window.height), 0, 1);
+
+		draw_rect :: proc(x, y, w, h: f32) {
+			gl.Begin(gl.TRIANGLES);
+			defer gl.End();
+
+			gl.Color3f(1, 0, 0); gl.Vertex3f(x,   y,   0);
+			gl.Color3f(0, 1, 0); gl.Vertex3f(x+w, y,   0);
+			gl.Color3f(0, 0, 1); gl.Vertex3f(x+w, y+h, 0);
+
+			gl.Color3f(0, 0, 1); gl.Vertex3f(x+w, y+h, 0);
+			gl.Color3f(1, 1, 0); gl.Vertex3f(x,   y+h, 0);
+			gl.Color3f(1, 0, 0); gl.Vertex3f(x,   y,   0);
+		}
+
+		draw_rect(pos.x, pos.y, 50, 50);
+
+		display_window(&window);
+		if ms_to_sleep := i32(16 - 1000*dt); ms_to_sleep > 0 {
+			win32.sleep(ms_to_sleep);
+		}
+	}
+}
+
+
+main :: proc() {
+	run();
+}