DragImageCairoWin.cpp [plain text]
#include "config.h"
#include "DragImage.h"
#include "BitmapInfo.h"
#include "CachedImage.h"
#include "GraphicsContext.h"
#include "GraphicsContextPlatformPrivateCairo.h"
#include "HWndDC.h"
#include "Image.h"
#include <cairo-win32.h>
#include <windows.h>
#include <wtf/RetainPtr.h>
#include <wtf/win/GDIObject.h>
namespace WebCore {
void deallocContext(PlatformContextCairo* target)
{
delete target;
}
GDIObject<HBITMAP> allocImage(HDC dc, IntSize size, PlatformContextCairo** targetRef)
{
BitmapInfo bmpInfo = BitmapInfo::create(size);
LPVOID bits;
auto hbmp = adoptGDIObject(::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)
return GDIObject<HBITMAP>();
cairo_t* cr = 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(cr, &matrix);
*targetRef = new PlatformGraphicsContext(cr);
cairo_destroy(cr);
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 imageRef, FloatSize scale)
{
if (!imageRef)
return 0;
GDIObject<HBITMAP> hbmp;
auto image = adoptGDIObject(imageRef);
IntSize srcSize = dragImageSize(image.get());
IntSize dstSize(static_cast<int>(srcSize.width() * scale.width()), static_cast<int>(srcSize.height() * scale.height()));
HWndDC dc(0);
auto dstDC = adoptGDIObject(::CreateCompatibleDC(dc));
if (!dstDC)
goto exit;
PlatformContextCairo* targetContext;
hbmp = allocImage(dstDC.get(), dstSize, &targetContext);
if (!hbmp)
goto exit;
cairo_surface_t* srcImage = createCairoContextFromBitmap(image.get());
cairo_t* cr = targetContext->cr();
cairo_translate(cr, 0, dstSize.height());
cairo_scale(cr, scale.width(), -scale.height());
cairo_set_source_surface(cr, srcImage, 0.0, 0.0);
cairo_paint(cr);
cairo_surface_destroy(srcImage);
deallocContext(targetContext);
exit:
if (!hbmp)
hbmp.swap(image);
return hbmp.leak();
}
DragImageRef createDragImageFromImage(Image* img, ImageOrientationDescription)
{
HWndDC dc(0);
auto workingDC = adoptGDIObject(::CreateCompatibleDC(dc));
if (!workingDC)
return 0;
PlatformContextCairo* drawContext = 0;
auto hbmp = allocImage(workingDC.get(), IntSize(img->size()), &drawContext);
if (!hbmp || !drawContext)
return 0;
cairo_t* cr = drawContext->cr();
cairo_set_source_rgb(cr, 1.0, 0.0, 1.0);
cairo_fill_preserve(cr);
RefPtr<cairo_surface_t> surface = img->nativeImageForCurrentFrame();
if (surface) {
cairo_set_source_surface(cr, surface.get(), 0.0, 0.0);
cairo_paint(cr);
}
deallocContext(drawContext);
return hbmp.leak();
}
}