robotgo/screen/screengrab_init.h

#include "screengrab.h"
#include "../base/bmp_io_init.h"
#include "../base/endian.h"
#include <stdlib.h> /* malloc() */

#if defined(IS_MACOSX)
	#include <OpenGL/OpenGL.h>
	#include <OpenGL/gl.h>
	#include <ApplicationServices/ApplicationServices.h>
#elif defined(USE_X11)
	#include <X11/Xlib.h>
	#include <X11/Xutil.h>
	#include "../base/xdisplay_init.h"
#elif defined(IS_WINDOWS)
	// #include "windows.h"
	// #include <wingdi.h>
	#include <string.h>
#endif

MMBitmapRef copyMMBitmapFromDisplayInRect(MMRect rect)
{
#if defined(IS_MACOSX)

	size_t bytewidth;
	uint8_t bitsPerPixel, bytesPerPixel;
	//uint8_t *buffer;

	CGDirectDisplayID displayID = CGMainDisplayID();

	//Replacement for CGDisplayBitsPerPixel.
	CGDisplayModeRef mode = CGDisplayCopyDisplayMode(displayID);
	size_t depth = 0;

	CFStringRef pixEnc = CGDisplayModeCopyPixelEncoding(mode);
	if(CFStringCompare(pixEnc, CFSTR(IO32BitDirectPixels), kCFCompareCaseInsensitive) == kCFCompareEqualTo)
		depth = 32;
	else if(CFStringCompare(pixEnc, CFSTR(IO16BitDirectPixels), kCFCompareCaseInsensitive) == kCFCompareEqualTo)
		depth = 16;
	else if(CFStringCompare(pixEnc, CFSTR(IO8BitIndexedPixels), kCFCompareCaseInsensitive) == kCFCompareEqualTo)
		depth = 8;

	CGDisplayModeRelease(mode);
	CFRelease(pixEnc);

	bitsPerPixel = (uint8_t) depth;
	bytesPerPixel = bitsPerPixel / 8;
	/* Align width to padding. */
	//bytewidth = ADD_PADDING(rect.size.width * bytesPerPixel);
	bytewidth = rect.size.width * bytesPerPixel;

	/* Convert Quartz point to postscript point. */
	//rect.origin.y = CGDisplayPixelsHigh(displayID) - rect.origin.y - rect.size.height;

	CGImageRef image = CGDisplayCreateImageForRect(displayID, CGRectMake(rect.origin.x, rect.origin.y, rect.size.width, rect.size.height));

    // Request access to the raw pixel data via the image's DataProvider.
    CGDataProviderRef provider = CGImageGetDataProvider(image);
    CFDataRef data = CGDataProviderCopyData(provider);

    size_t width, height;
    width = CGImageGetWidth(image);
    height = CGImageGetHeight(image);
    size_t bpp = CGImageGetBitsPerPixel(image) / 8;

    uint8 *pixels = malloc(width * height * bpp);
    memcpy(pixels, CFDataGetBytePtr(data), width * height * bpp);
    CFRelease(data);
   	CGImageRelease(image);

	return createMMBitmap(pixels, rect.size.width, rect.size.height, bytewidth,
	                      bitsPerPixel, bytesPerPixel);
#elif defined(USE_X11)
	MMBitmapRef bitmap;

	Display *display = XOpenDisplay(NULL);
	XImage *image = XGetImage(display,
	                          XDefaultRootWindow(display),
	                          (int)rect.origin.x,
	                          (int)rect.origin.y,
	                          (unsigned int)rect.size.width,
	                          (unsigned int)rect.size.height,
	                          AllPlanes, ZPixmap);
	XCloseDisplay(display);
	if (image == NULL) return NULL;

	bitmap = createMMBitmap((uint8_t *)image->data,
	                        rect.size.width,
	                        rect.size.height,
	                        (size_t)image->bytes_per_line,
	                        (uint8_t)image->bits_per_pixel,
	                        (uint8_t)image->bits_per_pixel / 8);
	image->data = NULL; /* Steal ownership of bitmap data so we don't have to
	                     * copy it. */
	XDestroyImage(image);

	return bitmap;
#elif defined(IS_WINDOWS)
	MMBitmapRef bitmap;
	void *data;
	HDC screen = NULL, screenMem = NULL;
	HBITMAP dib;
	BITMAPINFO bi;

	/* Initialize bitmap info. */
	bi.bmiHeader.biSize = sizeof(bi.bmiHeader);
   	bi.bmiHeader.biWidth = (long)rect.size.width;
   	bi.bmiHeader.biHeight = -(long)rect.size.height; /* Non-cartesian, please */
   	bi.bmiHeader.biPlanes = 1;
   	bi.bmiHeader.biBitCount = 32;
   	bi.bmiHeader.biCompression = BI_RGB;
   	bi.bmiHeader.biSizeImage = (DWORD)(4 * rect.size.width * rect.size.height);
	bi.bmiHeader.biXPelsPerMeter = 0;
	bi.bmiHeader.biYPelsPerMeter = 0;
	bi.bmiHeader.biClrUsed = 0;
	bi.bmiHeader.biClrImportant = 0;

	screen = GetDC(NULL); /* Get entire screen */
	if (screen == NULL) return NULL;

	/* Get screen data in display device context. */
   	dib = CreateDIBSection(screen, &bi, DIB_RGB_COLORS, &data, NULL, 0);

	/* Copy the data into a bitmap struct. */
	if ((screenMem = CreateCompatibleDC(screen)) == NULL ||
	    SelectObject(screenMem, dib) == NULL ||
	    !BitBlt(screenMem,
	            (int)0,
	            (int)0,
	            (int)rect.size.width,
	            (int)rect.size.height,
				screen,
				rect.origin.x,
				rect.origin.y,
				SRCCOPY)) {

		/* Error copying data. */
		ReleaseDC(NULL, screen);
		DeleteObject(dib);
		if (screenMem != NULL) DeleteDC(screenMem);

		return NULL;
	}

	bitmap = createMMBitmap(NULL,
	                        rect.size.width,
	                        rect.size.height,
	                        4 * rect.size.width,
	                        (uint8_t)bi.bmiHeader.biBitCount,
	                        4);

	/* Copy the data to our pixel buffer. */
	if (bitmap != NULL) {
		bitmap->imageBuffer = malloc(bitmap->bytewidth * bitmap->height);
		memcpy(bitmap->imageBuffer, data, bitmap->bytewidth * bitmap->height);
	}

	ReleaseDC(NULL, screen);
	DeleteObject(dib);
	DeleteDC(screenMem);

	return bitmap;
#endif
}