DragImageCGWin.cpp [plain text]
#include "config.h"
#include "DragImage.h"
#include "BitmapInfo.h"
#include "CachedImage.h"
#include "GraphicsContext.h"
#include "Image.h"
#include "RetainPtr.h"
#include <CoreGraphics/CoreGraphics.h>
#include <windows.h>
namespace WebCore {
void deallocContext(CGContextRef target)
{
CGContextRelease(target);
}
HBITMAP allocImage(HDC dc, IntSize size, CGContextRef *targetRef)
{
BitmapInfo bmpInfo = BitmapInfo::create(size);
LPVOID bits;
HBITMAP hbmp = CreateDIBSection(dc, &bmpInfo, DIB_RGB_COLORS, &bits, 0, 0);
if (!targetRef)
return hbmp;
CGColorSpaceRef deviceRGB = CGColorSpaceCreateDeviceRGB();
CGContextRef bitmapContext = CGBitmapContextCreate(bits, bmpInfo.bmiHeader.biWidth, bmpInfo.bmiHeader.biHeight, 8,
bmpInfo.bmiHeader.biWidth * 4, deviceRGB,
kCGBitmapByteOrder32Little | kCGImageAlphaNoneSkipFirst);
CGColorSpaceRelease(deviceRGB);
if (!bitmapContext) {
DeleteObject(hbmp);
return 0;
}
*targetRef = bitmapContext;
return hbmp;
}
static CGContextRef createCgContextFromBitmap(HBITMAP bitmap)
{
BITMAP info;
GetObject(bitmap, sizeof(info), &info);
ASSERT(info.bmBitsPixel == 32);
CGColorSpaceRef deviceRGB = CGColorSpaceCreateDeviceRGB();
CGContextRef bitmapContext = CGBitmapContextCreate(info.bmBits, info.bmWidth, info.bmHeight, 8,
info.bmWidthBytes, deviceRGB, kCGBitmapByteOrder32Little | kCGImageAlphaNoneSkipFirst);
CGColorSpaceRelease(deviceRGB);
return bitmapContext;
}
DragImageRef scaleDragImage(DragImageRef image, FloatSize scale)
{
if (!image)
return 0;
CGContextRef targetContext;
CGContextRef srcContext;
CGImageRef srcImage;
IntSize srcSize = dragImageSize(image);
IntSize dstSize(static_cast<int>(srcSize.width() * scale.width()), static_cast<int>(srcSize.height() * scale.height()));
HBITMAP hbmp = 0;
HDC dc = GetDC(0);
HDC dstDC = CreateCompatibleDC(dc);
if (!dstDC)
goto exit;
hbmp = allocImage(dstDC, dstSize, &targetContext);
if (!hbmp)
goto exit;
srcContext = createCgContextFromBitmap(image);
srcImage = CGBitmapContextCreateImage(srcContext);
CGRect rect;
rect.origin.x = 0;
rect.origin.y = 0;
rect.size = dstSize;
CGContextDrawImage(targetContext, rect, srcImage);
CGImageRelease(srcImage);
CGContextRelease(srcContext);
CGContextRelease(targetContext);
::DeleteObject(image);
image = 0;
exit:
if (!hbmp)
hbmp = image;
if (dstDC)
DeleteDC(dstDC);
ReleaseDC(0, dc);
return hbmp;
}
DragImageRef createDragImageFromImage(Image* img)
{
HBITMAP hbmp = 0;
HDC dc = GetDC(0);
HDC workingDC = CreateCompatibleDC(dc);
CGContextRef drawContext = 0;
if (!workingDC)
goto exit;
hbmp = allocImage(workingDC, img->size(), &drawContext);
if (!hbmp)
goto exit;
if (!drawContext) {
::DeleteObject(hbmp);
hbmp = 0;
}
CGImageRef srcImage = img->getCGImageRef();
CGRect rect;
rect.size = img->size();
rect.origin.x = 0;
rect.origin.y = -rect.size.height;
static const CGFloat white [] = {1.0, 1.0, 1.0, 1.0};
CGContextScaleCTM(drawContext, 1, -1);
CGContextSetFillColor(drawContext, white);
CGContextFillRect(drawContext, rect);
CGContextSetBlendMode(drawContext, kCGBlendModeNormal);
CGContextDrawImage(drawContext, rect, srcImage);
CGContextRelease(drawContext);
exit:
if (workingDC)
DeleteDC(workingDC);
ReleaseDC(0, dc);
return hbmp;
}
}