+ M_IMGDATA->m_maskGreen,
+ M_IMGDATA->m_maskBlue );
+ }
+
+ // In case this is a cursor, make sure the hotspot is scaled accordingly:
+ if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_X) )
+ image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X,
+ (GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X)*width)/old_width);
+ if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y) )
+ image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y,
+ (GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_Y)*height)/old_height);
+
+ return image;
+}
+
+wxImage wxImage::ResampleNearest(int width, int height) const
+{
+ wxImage image;
+ image.Create( width, height, false );
+
+ unsigned char *data = image.GetData();
+
+ wxCHECK_MSG( data, image, wxT("unable to create image") );
+
+ const unsigned char *source_data = M_IMGDATA->m_data;
+ unsigned char *target_data = data;
+ const unsigned char *source_alpha = 0 ;
+ unsigned char *target_alpha = 0 ;
+
+ if ( !M_IMGDATA->m_hasMask )
+ {
+ source_alpha = M_IMGDATA->m_alpha ;
+ if ( source_alpha )
+ {
+ image.SetAlpha() ;
+ target_alpha = image.GetAlpha() ;
+ }
+ }
+
+ long old_height = M_IMGDATA->m_height,
+ old_width = M_IMGDATA->m_width;
+ long x_delta = (old_width<<16) / width;
+ long y_delta = (old_height<<16) / height;
+
+ unsigned char* dest_pixel = target_data;
+
+ long y = 0;
+ for ( long j = 0; j < height; j++ )
+ {
+ const unsigned char* src_line = &source_data[(y>>16)*old_width*3];
+ const unsigned char* src_alpha_line = source_alpha ? &source_alpha[(y>>16)*old_width] : 0 ;
+
+ long x = 0;
+ for ( long i = 0; i < width; i++ )
+ {
+ const unsigned char* src_pixel = &src_line[(x>>16)*3];
+ const unsigned char* src_alpha_pixel = source_alpha ? &src_alpha_line[(x>>16)] : 0 ;
+ dest_pixel[0] = src_pixel[0];
+ dest_pixel[1] = src_pixel[1];
+ dest_pixel[2] = src_pixel[2];
+ dest_pixel += 3;
+ if ( source_alpha )
+ *(target_alpha++) = *src_alpha_pixel ;
+ x += x_delta;
+ }
+
+ y += y_delta;
+ }
+
+ return image;
+}
+
+wxImage wxImage::ResampleBox(int width, int height) const
+{
+ // This function implements a simple pre-blur/box averaging method for
+ // downsampling that gives reasonably smooth results To scale the image
+ // down we will need to gather a grid of pixels of the size of the scale
+ // factor in each direction and then do an averaging of the pixels.
+
+ wxImage ret_image(width, height, false);
+
+ const double scale_factor_x = double(M_IMGDATA->m_width) / width;
+ const double scale_factor_y = double(M_IMGDATA->m_height) / height;
+
+ const int scale_factor_x_2 = (int)(scale_factor_x / 2);
+ const int scale_factor_y_2 = (int)(scale_factor_y / 2);
+
+ const unsigned char* src_data = M_IMGDATA->m_data;
+ const unsigned char* src_alpha = M_IMGDATA->m_alpha;
+ unsigned char* dst_data = ret_image.GetData();
+ unsigned char* dst_alpha = NULL;
+
+ if ( src_alpha )
+ {
+ ret_image.SetAlpha();
+ dst_alpha = ret_image.GetAlpha();
+ }
+
+ int averaged_pixels, src_pixel_index;
+ double sum_r, sum_g, sum_b, sum_a;
+
+ for ( int y = 0; y < height; y++ ) // Destination image - Y direction
+ {
+ // Source pixel in the Y direction
+ int src_y = (int)(y * scale_factor_y);
+
+ for ( int x = 0; x < width; x++ ) // Destination image - X direction
+ {
+ // Source pixel in the X direction
+ int src_x = (int)(x * scale_factor_x);
+
+ // Box of pixels to average
+ averaged_pixels = 0;
+ sum_r = sum_g = sum_b = sum_a = 0.0;
+
+ for ( int j = int(src_y - scale_factor_y/2.0 + 1), k = j;
+ j <= int(src_y + scale_factor_y_2) || j < k + 2;
+ j++ )
+ {
+ // We don't care to average pixels that don't exist (edges)
+ if ( j < 0 || j > M_IMGDATA->m_height - 1 )
+ continue;
+
+ for ( int i = int(src_x - scale_factor_x/2.0 + 1), e = i;
+ i <= src_x + scale_factor_x_2 || i < e + 2;
+ i++ )
+ {
+ // Don't average edge pixels
+ if ( i < 0 || i > M_IMGDATA->m_width - 1 )
+ continue;
+
+ // Calculate the actual index in our source pixels
+ src_pixel_index = j * M_IMGDATA->m_width + i;
+
+ sum_r += src_data[src_pixel_index * 3 + 0];
+ sum_g += src_data[src_pixel_index * 3 + 1];
+ sum_b += src_data[src_pixel_index * 3 + 2];
+ if ( src_alpha )
+ sum_a += src_alpha[src_pixel_index];
+
+ averaged_pixels++;
+ }
+ }
+
+ // Calculate the average from the sum and number of averaged pixels
+ dst_data[0] = (unsigned char)(sum_r / averaged_pixels);
+ dst_data[1] = (unsigned char)(sum_g / averaged_pixels);
+ dst_data[2] = (unsigned char)(sum_b / averaged_pixels);
+ dst_data += 3;
+ if ( src_alpha )
+ *dst_alpha++ = (unsigned char)(sum_a / averaged_pixels);
+ }
+ }
+
+ return ret_image;
+}
+
+wxImage wxImage::ResampleBilinear(int width, int height) const
+{
+ // This function implements a Bilinear algorithm for resampling.
+ wxImage ret_image(width, height, false);
+ const unsigned char* src_data = M_IMGDATA->m_data;
+ const unsigned char* src_alpha = M_IMGDATA->m_alpha;
+ unsigned char* dst_data = ret_image.GetData();
+ unsigned char* dst_alpha = NULL;
+
+ if ( src_alpha )
+ {
+ ret_image.SetAlpha();
+ dst_alpha = ret_image.GetAlpha();
+ }
+ double HFactor = double(M_IMGDATA->m_height) / height;
+ double WFactor = double(M_IMGDATA->m_width) / width;
+
+ int srcpixymax = M_IMGDATA->m_height - 1;
+ int srcpixxmax = M_IMGDATA->m_width - 1;
+
+ double srcpixy, srcpixy1, srcpixy2, dy, dy1;
+ double srcpixx, srcpixx1, srcpixx2, dx, dx1;
+
+ // initialize alpha values to avoid g++ warnings about possibly
+ // uninitialized variables
+ double r1, g1, b1, a1 = 0;
+ double r2, g2, b2, a2 = 0;
+
+ for ( int dsty = 0; dsty < height; dsty++ )
+ {
+ // We need to calculate the source pixel to interpolate from - Y-axis
+ srcpixy = double(dsty) * HFactor;
+ srcpixy1 = int(srcpixy);
+ srcpixy2 = ( srcpixy1 == srcpixymax ) ? srcpixy1 : srcpixy1 + 1.0;
+ dy = srcpixy - (int)srcpixy;
+ dy1 = 1.0 - dy;
+
+
+ for ( int dstx = 0; dstx < width; dstx++ )
+ {
+ // X-axis of pixel to interpolate from
+ srcpixx = double(dstx) * WFactor;
+ srcpixx1 = int(srcpixx);
+ srcpixx2 = ( srcpixx1 == srcpixxmax ) ? srcpixx1 : srcpixx1 + 1.0;
+ dx = srcpixx - (int)srcpixx;
+ dx1 = 1.0 - dx;
+
+ int x_offset1 = srcpixx1 < 0.0 ? 0 : srcpixx1 > srcpixxmax ? srcpixxmax : (int)srcpixx1;
+ int x_offset2 = srcpixx2 < 0.0 ? 0 : srcpixx2 > srcpixxmax ? srcpixxmax : (int)srcpixx2;
+ int y_offset1 = srcpixy1 < 0.0 ? 0 : srcpixy1 > srcpixymax ? srcpixymax : (int)srcpixy1;
+ int y_offset2 = srcpixy2 < 0.0 ? 0 : srcpixy2 > srcpixymax ? srcpixymax : (int)srcpixy2;
+
+ int src_pixel_index00 = y_offset1 * M_IMGDATA->m_width + x_offset1;
+ int src_pixel_index01 = y_offset1 * M_IMGDATA->m_width + x_offset2;
+ int src_pixel_index10 = y_offset2 * M_IMGDATA->m_width + x_offset1;
+ int src_pixel_index11 = y_offset2 * M_IMGDATA->m_width + x_offset2;
+
+ // first line
+ r1 = src_data[src_pixel_index00 * 3 + 0] * dx1 + src_data[src_pixel_index01 * 3 + 0] * dx;
+ g1 = src_data[src_pixel_index00 * 3 + 1] * dx1 + src_data[src_pixel_index01 * 3 + 1] * dx;
+ b1 = src_data[src_pixel_index00 * 3 + 2] * dx1 + src_data[src_pixel_index01 * 3 + 2] * dx;
+ if ( src_alpha )
+ a1 = src_alpha[src_pixel_index00] * dx1 + src_alpha[src_pixel_index01] * dx;
+
+ // second line
+ r2 = src_data[src_pixel_index10 * 3 + 0] * dx1 + src_data[src_pixel_index11 * 3 + 0] * dx;
+ g2 = src_data[src_pixel_index10 * 3 + 1] * dx1 + src_data[src_pixel_index11 * 3 + 1] * dx;
+ b2 = src_data[src_pixel_index10 * 3 + 2] * dx1 + src_data[src_pixel_index11 * 3 + 2] * dx;
+ if ( src_alpha )
+ a2 = src_alpha[src_pixel_index10] * dx1 + src_alpha[src_pixel_index11] * dx;
+
+ // result lines
+
+ dst_data[0] = static_cast<unsigned char>(r1 * dy1 + r2 * dy);
+ dst_data[1] = static_cast<unsigned char>(g1 * dy1 + g2 * dy);
+ dst_data[2] = static_cast<unsigned char>(b1 * dy1 + b2 * dy);
+ dst_data += 3;
+
+ if ( src_alpha )
+ *dst_alpha++ = static_cast<unsigned char>(a1 * dy1 + a2 * dy);
+ }