DragImageCairoWin.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 <cairo-win32.h>
#include "GraphicsContextPlatformPrivateCairo.h"
#include <windows.h>
extern "C" {
typedef struct _cairo* CairoContextRef;
}
namespace WebCore {
void deallocContext(CairoContextRef target)
{
cairo_destroy(target);
}
HBITMAP allocImage(HDC dc, IntSize size, CairoContextRef* targetRef)
{
BitmapInfo bmpInfo = BitmapInfo::create(size);
LPVOID bits;
HBITMAP hbmp = CreateDIBSection(dc, &bmpInfo, DIB_RGB_COLORS, &bits, 0, 0);
if (!targetRef)
return hbmp;
cairo_surface_t* bitmapContext = cairo_image_surface_create_for_data((unsigned char*)bits,
CAIRO_FORMAT_ARGB32,
bmpInfo.bmiHeader.biWidth,
bmpInfo.bmiHeader.biHeight,
bmpInfo.bmiHeader.biWidth * 4);
if (!bitmapContext) {
DeleteObject(hbmp);
return 0;
}
*targetRef = cairo_create (bitmapContext);
cairo_surface_destroy (bitmapContext);
cairo_matrix_t matrix;
cairo_matrix_init(&matrix, 1.0, 0.0, 0.0, -1.0, 0.0, size.height());
cairo_set_matrix(*targetRef, &matrix);
return hbmp;
}
static cairo_surface_t* createCairoContextFromBitmap(HBITMAP bitmap)
{
BITMAP info;
GetObject(bitmap, sizeof(info), &info);
ASSERT(info.bmBitsPixel == 32);
return cairo_image_surface_create_for_data((unsigned char*)info.bmBits,
CAIRO_FORMAT_ARGB32,
info.bmWidth,
info.bmHeight,
info.bmWidthBytes);
}
DragImageRef scaleDragImage(DragImageRef image, FloatSize scale)
{
if (!image)
return 0;
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;
CairoContextRef targetContext;
hbmp = allocImage(dstDC, dstSize, &targetContext);
if (!hbmp)
goto exit;
cairo_surface_t* srcImage = createCairoContextFromBitmap(image);
cairo_translate(targetContext, 0, dstSize.height());
cairo_scale(targetContext, scale.width(), -scale.height());
cairo_set_source_surface (targetContext, srcImage, 0.0, 0.0);
cairo_paint(targetContext);
cairo_surface_destroy (srcImage);
cairo_destroy(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);
if (!workingDC)
goto exit;
CairoContextRef drawContext = 0;
hbmp = allocImage(workingDC, img->size(), &drawContext);
if (!hbmp)
goto exit;
if (!drawContext) {
::DeleteObject(hbmp);
hbmp = 0;
}
cairo_set_source_rgb (drawContext, 1.0, 0.0, 1.0);
cairo_fill_preserve (drawContext);
cairo_surface_t* srcImage = img->nativeImageForCurrentFrame();
cairo_set_source_surface(drawContext, srcImage, 0.0, 0.0);
cairo_paint(drawContext);
cairo_destroy (drawContext);
exit:
if (workingDC)
DeleteDC(workingDC);
ReleaseDC(0, dc);
return hbmp;
}
}