RGBQUAD CxDib::GetPixelColor(long x,long y)
{
RGBQUAD rgb={0,0,0,0};
if ((hDib==NULL)||(x<0)||(y<0)||
(x>=m_bi.biWidth)||(y>=m_bi.biHeight)) return rgb;
if (m_nColors) return GetPaletteIndex(GetPixelIndex(x,y));
else {
BYTE* iDst = GetBits()+(m_bi.biHeight - y)*m_LineWidth + x*sizeof(RGBQUAD);
rgb.rgbBlue = *iDst++;
rgb.rgbGreen= *iDst++;
rgb.rgbRed =*iDst;
return rgb;
}
}
/** @brief Fills a FIT_BITMAP image with the specified color.
This function does the dirty work for FreeImage_FillBackground for FIT_BITMAP
images.
@param dib The image to be filled.
@param color The color, the specified image should be filled with.
@param options Options that affect the color search process for palletized images.
@return Returns TRUE on success, FALSE otherwise. This function fails if any of
the dib and color is NULL or the provided image is not a FIT_BITMAP image.
*/
static BOOL
FillBackgroundBitmap(FIBITMAP *dib, const RGBQUAD *color, int options) {
if ((!dib) || (FreeImage_GetImageType(dib) != FIT_BITMAP)) {
return FALSE;;
}
if (!color) {
return FALSE;
}
const RGBQUAD *color_intl = color;
unsigned bpp = FreeImage_GetBPP(dib);
unsigned width = FreeImage_GetWidth(dib);
unsigned height = FreeImage_GetHeight(dib);
FREE_IMAGE_COLOR_TYPE color_type = FreeImage_GetColorType(dib);
// get a pointer to the first scanline (bottom line)
BYTE *src_bits = FreeImage_GetScanLine(dib, 0);
BYTE *dst_bits = src_bits;
BOOL supports_alpha = ((bpp >= 24) || ((bpp == 8) && (color_type != FIC_PALETTE)));
// Check for RGBA case if bitmap supports alpha
// blending (8-bit greyscale, 24- or 32-bit images)
if (supports_alpha && (options & FI_COLOR_IS_RGBA_COLOR)) {
if (color->rgbReserved == 0) {
// the fill color is fully transparent; we are done
return TRUE;
}
// Only if the fill color is NOT fully opaque, draw it with
// the (much) slower FreeImage_DrawLine function and return.
// Since we do not have the FreeImage_DrawLine function in this
// release, just assume to have an unicolor background and fill
// all with an 'alpha-blended' color.
if (color->rgbReserved < 255) {
// If we will draw on an unicolor background, it's
// faster to draw opaque with an alpha blended color.
// So, first get the color from the first pixel in the
// image (bottom-left pixel).
RGBQUAD bgcolor;
if (bpp == 8) {
bgcolor = FreeImage_GetPalette(dib)[*src_bits];
} else {
bgcolor.rgbBlue = src_bits[FI_RGBA_BLUE];
bgcolor.rgbGreen = src_bits[FI_RGBA_GREEN];
bgcolor.rgbRed = src_bits[FI_RGBA_RED];
bgcolor.rgbReserved = 0xFF;
}
RGBQUAD blend;
GetAlphaBlendedColor(&bgcolor, color_intl, &blend);
color_intl = &blend;
}
}
int index = (bpp <= 8) ? GetPaletteIndex(dib, color_intl, options, &color_type) : 0;
if (index == -1) {
// No palette index found for a palletized
// image. This should never happen...
return FALSE;
}
// first, build the first scanline (line 0)
switch (bpp) {
case 1: {
unsigned bytes = (width / 8);
memset(dst_bits, ((index == 1) ? 0xFF : 0x00), bytes);
//int n = width % 8;
int n = width & 7;
if (n) {
if (index == 1) {
// set n leftmost bits
dst_bits[bytes] |= (0xFF << (8 - n));
} else {
// clear n leftmost bits
dst_bits[bytes] &= (0xFF >> n);
}
}
break;
}
case 4: {
unsigned bytes = (width / 2);
memset(dst_bits, (index | (index << 4)), bytes);
//if (bytes % 2) {
if (bytes & 1) {
dst_bits[bytes] &= 0x0F;
dst_bits[bytes] |= (index << 4);
}
break;
}
case 8: {
memset(dst_bits, index, FreeImage_GetLine(dib));
break;
}
case 16: {
WORD wcolor = RGBQUAD_TO_WORD(dib, color_intl);
for (unsigned x = 0; x < width; x++) {
((WORD *)dst_bits)[x] = wcolor;
}
break;
}
case 24: {
RGBTRIPLE rgbt = *((RGBTRIPLE *)color_intl);
for (unsigned x = 0; x < width; x++) {
((RGBTRIPLE *)dst_bits)[x] = rgbt;
}
break;
}
case 32: {
RGBQUAD rgbq;
rgbq.rgbBlue = ((RGBTRIPLE *)color_intl)->rgbtBlue;
rgbq.rgbGreen = ((RGBTRIPLE *)color_intl)->rgbtGreen;
rgbq.rgbRed = ((RGBTRIPLE *)color_intl)->rgbtRed;
rgbq.rgbReserved = 0xFF;
for (unsigned x = 0; x < width; x++) {
((RGBQUAD *)dst_bits)[x] = rgbq;
}
break;
}
default:
return FALSE;
}
// Then, copy the first scanline into all following scanlines.
// 'src_bits' is a pointer to the first scanline and is already
// set up correctly.
if (src_bits) {
unsigned pitch = FreeImage_GetPitch(dib);
unsigned bytes = FreeImage_GetLine(dib);
dst_bits = src_bits + pitch;
for (unsigned y = 1; y < height; y++) {
memcpy(dst_bits, src_bits, bytes);
dst_bits += pitch;
}
}
return TRUE;
}
