func handleUpload(hwnd win32.HWND, uMsg uint32, wParam, lParam uintptr) {
id := wParam
uploadsMu.Lock()
u := uploads[id]
delete(uploads, id)
uploadsMu.Unlock()
dc, err := win32.GetDC(hwnd)
if err != nil {
panic(err) // TODO handle errors
}
defer win32.ReleaseDC(hwnd, dc)
u.src.preUpload(true)
// TODO: adjust if dp is outside dst bounds, or sr is outside src bounds.
err = blit(dc, _POINT{int32(u.dp.X), int32(u.dp.Y)}, u.src.hbitmap, &_RECT{
Left: int32(u.sr.Min.X),
Top: int32(u.sr.Min.Y),
Right: int32(u.sr.Max.X),
Bottom: int32(u.sr.Max.Y),
})
go func() {
u.src.postUpload()
close(u.completion)
}()
if err != nil {
panic(err) // TODO handle errors
}
}
func fillSrc(hwnd win32.HWND, uMsg uint32, wParam, lParam uintptr) {
dc, err := win32.GetDC(hwnd)
if err != nil {
panic(err) // TODO handle error?
}
defer win32.ReleaseDC(hwnd, dc)
r := (*_RECT)(unsafe.Pointer(lParam))
color := _COLORREF(wParam)
// COLORREF is 0x00BBGGRR; color is 0xAARRGGBB
color = _RGB(byte((color >> 16)), byte((color >> 8)), byte(color))
brush, err := _CreateSolidBrush(color)
if err != nil {
panic(err) // TODO handle error
}
defer _DeleteObject(brush)
err = _FillRect(dc, r, brush)
if err != nil {
panic(err) // TODO handle error
}
}
func fillOver(hwnd win32.HWND, uMsg uint32, wParam, lParam uintptr) {
dc, err := win32.GetDC(hwnd)
if err != nil {
panic(err) // TODO handle error
}
defer win32.ReleaseDC(hwnd, dc)
r := (*_RECT)(unsafe.Pointer(lParam))
color := _COLORREF(wParam)
// AlphaBlend will stretch the input image (using StretchBlt's
// COLORONCOLOR mode) to fill the output rectangle. Testing
// this shows that the result appears to be the same as if we had
// used a MxN bitmap instead.
bitmap, bitvalues, err := mkbitmap(1, 1)
if err != nil {
panic(err) // TODO handle error
}
defer _DeleteObject(bitmap) // TODO handle error?
*(*_COLORREF)(unsafe.Pointer(bitvalues)) = color
if err = blend(dc, bitmap, r, 1, 1); err != nil {
panic(err) // TODO handle error
}
}