opengl.c

#define GL_SILENCE_DEPRECATION
#define SILICON_IMPLEMENTATION
#include <silicon.h>

#include <OpenGL/gl.h>


CVReturn displayCallback(CVDisplayLinkRef displayLink, const CVTimeStamp *inNow, const CVTimeStamp *inOutputTime, CVOptionFlags flagsIn, CVOptionFlags *flagsOut, void *displayLinkContext) { return kCVReturnSuccess; }

bool is_running = true;

bool windowShouldClose(void* self)  {
	is_running = false;
	return true;
}


int main() {
	NSApplication* NSApp = NSApplication_sharedApplication();
	NSApplication_setActivationPolicy(NSApp, NSApplicationActivationPolicyRegular);

	// Convert C functions to Objective-C methods (refer to the 'si_func_to_SEL' comment from 'examples/menu.c' for more).
	si_func_to_SEL(SI_DEFAULT, windowShouldClose);

	NSWindow* win = NSWindow_init(NSMakeRect(100, 100, 512, 512), NSWindowStyleMaskTitled | NSWindowStyleMaskClosable | NSWindowStyleMaskResizable | NSWindowStyleMaskMiniaturizable, NSBackingStoreBuffered, false);
	NSWindow_setTitle(win, "OpenGL example");

	NSOpenGLPixelFormatAttribute attributes[] = {
		NSOpenGLPFANoRecovery,
		NSOpenGLPFAAccelerated,
		NSOpenGLPFADoubleBuffer,
		NSOpenGLPFAColorSize, 24,
		NSOpenGLPFAAlphaSize, 8,
		NSOpenGLPFADepthSize, 24,
		NSOpenGLPFAStencilSize, 8,
		0
	};
	CVDisplayLinkRef displayLink;
	NSOpenGLPixelFormat* format = NSOpenGLPixelFormat_initWithAttributes(attributes);
	NSOpenGLView* view = NSOpenGLView_initWithFrame(NSMakeRect(0, 0, 512, 512), format);
	NSOpenGLView_prepareOpenGL(view);


	GLint swapInt = 1;
	NSOpenGLContext* context = NSOpenGLView_openGLContext(view);
	NSOpenGLContext_setValues(context, &swapInt, NSOpenGLContextParameterSwapInterval);

	CGDirectDisplayID displayID = CGMainDisplayID();
	CVDisplayLinkCreateWithCGDisplay(displayID, &displayLink);
	CVDisplayLinkSetOutputCallback(displayLink, displayCallback, win);
	CVDisplayLinkStart(displayLink);

	NSOpenGLContext_makeCurrentContext(context);
	NSWindow_setContentView(win, (NSView*)view);
	NSWindow_setIsVisible(win, true);
	NSWindow_makeMainWindow(win);

	NSApplication_finishLaunching(NSApp);

	while (is_running) {
		// Get the Windows events.
		NSEvent* e = NSApplication_nextEventMatchingMask(NSApp, NSEventMaskAny, NSDate_distantFuture(), NSDefaultRunLoopMode, true);
		
		NSApplication_sendEvent(NSApp, e);
		NSApplication_updateWindows(NSApp);

		// Clear the screen
		glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
		glClear(GL_COLOR_BUFFER_BIT);

		// Draw a simple triangle.
		glBegin(GL_TRIANGLES);
			glColor3f(1, 0, 0); glVertex2f(-1.0f, -1.0f);
			glColor3f(0, 1, 0); glVertex2f( 1.0f, -1.0f);
			glColor3f(0, 0, 1); glVertex2f( 0.0f,  1.0f);
		glEnd();

		// Flush to buffer.
		NSOpenGLContext_flushBuffer(context);
	}

	CVDisplayLinkStop(displayLink);
	CVDisplayLinkRelease(displayLink);
	release(view);
	NSApplication_terminate(NSApp, (id)win);

	return 0;
}