- for( j=0; j<height; j++ )
- {
- for( i=0; i<width; i++ )
- {
- *(ptbits++) = *(ptdata+2);
- *(ptbits++) = *(ptdata+1);
- *(ptbits++) = *(ptdata );
- ptdata += 3;
- }
- for( i=0; i< padding; i++ ) *(ptbits++) = 0;
- }
- ::StretchDIBits( memdc, 0, origin, width, height,\
- 0, 0, width, height, lpBits, lpDIBh, DIB_RGB_COLORS, SRCCOPY);
- origin += height;
- // if numDIB = 1, lines below can also be used
- // hbitmap = CreateDIBitmap( hdc, &(lpDIBh->bmiHeader), CBM_INIT, lpBits, lpDIBh, DIB_RGB_COLORS );
- // The above line is equivalent to the following two lines.
- // hbitmap = ::CreateCompatibleBitmap( hdc, width, height );
- // ::SetDIBits( hdc, hbitmap, 0, height, lpBits, lpDIBh, DIB_RGB_COLORS);
- // or the following lines
- // hbitmap = ::CreateCompatibleBitmap( hdc, width, height );
- // HDC memdc = ::CreateCompatibleDC( hdc );
- // ::SelectObject( memdc, hbitmap);
- // ::SetDIBitsToDevice( memdc, 0, 0, width, height,
- // 0, 0, 0, height, (void *)lpBits, lpDIBh, DIB_RGB_COLORS);
- // ::SelectObject( memdc, 0 );
- // ::DeleteDC( memdc );
- }
- bitmap.SetHBITMAP( (WXHBITMAP) hbitmap );
-
- // similarly, created an mono-bitmap for the possible mask
- if( HasMask() )
- {
- hbitmap = ::CreateBitmap( (WORD)width, (WORD)bmpHeight, 1, 1, NULL );
- ::SelectObject( memdc, hbitmap);
- if( numDIB == 1 ) height = bmpHeight;
- else height = sizeLimit/bytePerLine;
- lpDIBh->bmiHeader.biHeight = (DWORD)(-height);
- lpDIBh->bmiHeader.biSizeImage = bytePerLine*height;
- origin = 0;
- unsigned char r = GetMaskRed();
- unsigned char g = GetMaskGreen();
- unsigned char b = GetMaskBlue();
- unsigned char zero = 0, one = 255;
- ptdata = data;
- for( n=0; n<numDIB; n++ )
- {
- if( numDIB > 1 && n == numDIB - 1 && hRemain > 0 )
- {
- // redefine height and size of the (possibly) last smaller DIB
- // memory is not reallocated
- height = hRemain;
- lpDIBh->bmiHeader.biHeight = (DWORD)(-height);
- lpDIBh->bmiHeader.biSizeImage = bytePerLine*height;
- }
- ptbits = lpBits;
- for( int j=0; j<height; j++ )
- {
- for(i=0; i<width; i++ )
- {
- if( (*(ptdata++)!=r) | (*(ptdata++)!=g) | (*(ptdata++)!=b) )
+ const double d1 = (src.x - x1) * (src.x - x1) + (src.y - y1) * (src.y - y1);
+ const double d2 = (src.x - x2) * (src.x - x2) + (src.y - y1) * (src.y - y1);
+ const double d3 = (src.x - x2) * (src.x - x2) + (src.y - y2) * (src.y - y2);
+ const double d4 = (src.x - x1) * (src.x - x1) + (src.y - y2) * (src.y - y2);
+
+ // Now interpolate as a weighted average of the four surrounding
+ // points, where the weights are the distances to each of those points
+
+ // If the point is exactly at one point of the grid of the source
+ // image, then don't interpolate -- just assign the pixel
+
+ if (d1 < gs_Epsilon) // d1,d2,d3,d4 are positive -- no need for abs()
+ {
+ unsigned char *p = data[y1] + (3 * x1);
+ *(dst++) = *(p++);
+ *(dst++) = *(p++);
+ *(dst++) = *p;
+
+ if (has_alpha)
+ {
+ unsigned char *p = alpha[y1] + x1;
+ *(alpha_dst++) = *p;
+ }
+ }
+ else if (d2 < gs_Epsilon)