+// The following two local functions are for the B-spline weighting of the
+// bicubic sampling algorithm
+static inline double spline_cube(double value)
+{
+ return value <= 0.0 ? 0.0 : value * value * value;
+}
+
+static inline double spline_weight(double value)
+{
+ return (spline_cube(value + 2) -
+ 4 * spline_cube(value + 1) +
+ 6 * spline_cube(value) -
+ 4 * spline_cube(value - 1)) / 6;
+}
+
+// This is the bicubic resampling algorithm
+wxImage wxImage::ResampleBicubic(int width, int height) const
+{
+ // This function implements a Bicubic B-Spline algorithm for resampling.
+ // This method is certainly a little slower than wxImage's default pixel
+ // replication method, however for most reasonably sized images not being
+ // upsampled too much on a fairly average CPU this difference is hardly
+ // noticeable and the results are far more pleasing to look at.
+ //
+ // This particular bicubic algorithm does pixel weighting according to a
+ // B-Spline that basically implements a Gaussian bell-like weighting
+ // kernel. Because of this method the results may appear a bit blurry when
+ // upsampling by large factors. This is basically because a slight
+ // gaussian blur is being performed to get the smooth look of the upsampled
+ // image.
+
+ // Edge pixels: 3-4 possible solutions
+ // - (Wrap/tile) Wrap the image, take the color value from the opposite
+ // side of the image.
+ // - (Mirror) Duplicate edge pixels, so that pixel at coordinate (2, n),
+ // where n is nonpositive, will have the value of (2, 1).
+ // - (Ignore) Simply ignore the edge pixels and apply the kernel only to
+ // pixels which do have all neighbours.
+ // - (Clamp) Choose the nearest pixel along the border. This takes the
+ // border pixels and extends them out to infinity.
+ //
+ // NOTE: below the y_offset and x_offset variables are being set for edge
+ // pixels using the "Mirror" method mentioned above
+
+ wxImage ret_image;
+
+ ret_image.Create(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();
+ }
+
+ for ( int dsty = 0; dsty < height; dsty++ )
+ {
+ // We need to calculate the source pixel to interpolate from - Y-axis
+ double srcpixy = double(dsty * M_IMGDATA->m_height) / height;
+ double dy = srcpixy - (int)srcpixy;
+
+ for ( int dstx = 0; dstx < width; dstx++ )
+ {
+ // X-axis of pixel to interpolate from
+ double srcpixx = double(dstx * M_IMGDATA->m_width) / width;
+ double dx = srcpixx - (int)srcpixx;
+
+ // Sums for each color channel
+ double sum_r = 0, sum_g = 0, sum_b = 0, sum_a = 0;
+
+ // Here we actually determine the RGBA values for the destination pixel
+ for ( int k = -1; k <= 2; k++ )
+ {
+ // Y offset
+ int y_offset = srcpixy + k < 0.0
+ ? 0
+ : srcpixy + k >= M_IMGDATA->m_height
+ ? M_IMGDATA->m_height - 1
+ : (int)(srcpixy + k);
+
+ // Loop across the X axis
+ for ( int i = -1; i <= 2; i++ )
+ {
+ // X offset
+ int x_offset = srcpixx + i < 0.0
+ ? 0
+ : srcpixx + i >= M_IMGDATA->m_width
+ ? M_IMGDATA->m_width - 1
+ : (int)(srcpixx + i);
+
+ // Calculate the exact position where the source data
+ // should be pulled from based on the x_offset and y_offset
+ int src_pixel_index = y_offset*M_IMGDATA->m_width + x_offset;
+
+ // Calculate the weight for the specified pixel according
+ // to the bicubic b-spline kernel we're using for
+ // interpolation
+ double
+ pixel_weight = spline_weight(i - dx)*spline_weight(k - dy);
+
+ // Create a sum of all velues for each color channel
+ // adjusted for the pixel's calculated weight
+ sum_r += src_data[src_pixel_index * 3 + 0] * pixel_weight;
+ sum_g += src_data[src_pixel_index * 3 + 1] * pixel_weight;
+ sum_b += src_data[src_pixel_index * 3 + 2] * pixel_weight;
+ if ( src_alpha )
+ sum_a += src_alpha[src_pixel_index] * pixel_weight;
+ }
+ }
+
+ // Put the data into the destination image. The summed values are
+ // of double data type and are rounded here for accuracy
+ dst_data[0] = (unsigned char)(sum_r + 0.5);
+ dst_data[1] = (unsigned char)(sum_g + 0.5);
+ dst_data[2] = (unsigned char)(sum_b + 0.5);
+ dst_data += 3;
+
+ if ( src_alpha )
+ *dst_alpha++ = (unsigned char)sum_a;
+ }
+ }
+
+ return ret_image;
+}
+
+// Blur in the horizontal direction
+wxImage wxImage::BlurHorizontal(int blurRadius) const
+{
+ wxImage ret_image(MakeEmptyClone());
+
+ wxCHECK( ret_image.IsOk(), ret_image );
+
+ const unsigned char* src_data = M_IMGDATA->m_data;
+ unsigned char* dst_data = ret_image.GetData();
+ const unsigned char* src_alpha = M_IMGDATA->m_alpha;
+ unsigned char* dst_alpha = ret_image.GetAlpha();
+
+ // number of pixels we average over
+ const int blurArea = blurRadius*2 + 1;
+
+ // Horizontal blurring algorithm - average all pixels in the specified blur
+ // radius in the X or horizontal direction
+ for ( int y = 0; y < M_IMGDATA->m_height; y++ )
+ {
+ // Variables used in the blurring algorithm
+ long sum_r = 0,
+ sum_g = 0,
+ sum_b = 0,
+ sum_a = 0;
+
+ long pixel_idx;
+ const unsigned char *src;
+ unsigned char *dst;
+
+ // Calculate the average of all pixels in the blur radius for the first
+ // pixel of the row
+ for ( int kernel_x = -blurRadius; kernel_x <= blurRadius; kernel_x++ )
+ {
+ // To deal with the pixels at the start of a row so it's not
+ // grabbing GOK values from memory at negative indices of the
+ // image's data or grabbing from the previous row
+ if ( kernel_x < 0 )
+ pixel_idx = y * M_IMGDATA->m_width;
+ else
+ pixel_idx = kernel_x + y * M_IMGDATA->m_width;
+
+ src = src_data + pixel_idx*3;
+ sum_r += src[0];
+ sum_g += src[1];
+ sum_b += src[2];
+ if ( src_alpha )
+ sum_a += src_alpha[pixel_idx];
+ }
+
+ dst = dst_data + y * M_IMGDATA->m_width*3;
+ dst[0] = (unsigned char)(sum_r / blurArea);
+ dst[1] = (unsigned char)(sum_g / blurArea);
+ dst[2] = (unsigned char)(sum_b / blurArea);
+ if ( src_alpha )
+ dst_alpha[y * M_IMGDATA->m_width] = (unsigned char)(sum_a / blurArea);
+
+ // Now average the values of the rest of the pixels by just moving the
+ // blur radius box along the row
+ for ( int x = 1; x < M_IMGDATA->m_width; x++ )
+ {
+ // Take care of edge pixels on the left edge by essentially
+ // duplicating the edge pixel
+ if ( x - blurRadius - 1 < 0 )
+ pixel_idx = y * M_IMGDATA->m_width;
+ else
+ pixel_idx = (x - blurRadius - 1) + y * M_IMGDATA->m_width;
+
+ // Subtract the value of the pixel at the left side of the blur
+ // radius box
+ src = src_data + pixel_idx*3;
+ sum_r -= src[0];
+ sum_g -= src[1];
+ sum_b -= src[2];
+ if ( src_alpha )
+ sum_a -= src_alpha[pixel_idx];
+
+ // Take care of edge pixels on the right edge
+ if ( x + blurRadius > M_IMGDATA->m_width - 1 )
+ pixel_idx = M_IMGDATA->m_width - 1 + y * M_IMGDATA->m_width;
+ else
+ pixel_idx = x + blurRadius + y * M_IMGDATA->m_width;
+
+ // Add the value of the pixel being added to the end of our box
+ src = src_data + pixel_idx*3;
+ sum_r += src[0];
+ sum_g += src[1];
+ sum_b += src[2];
+ if ( src_alpha )
+ sum_a += src_alpha[pixel_idx];
+
+ // Save off the averaged data
+ dst = dst_data + x*3 + y*M_IMGDATA->m_width*3;
+ dst[0] = (unsigned char)(sum_r / blurArea);
+ dst[1] = (unsigned char)(sum_g / blurArea);
+ dst[2] = (unsigned char)(sum_b / blurArea);
+ if ( src_alpha )
+ dst_alpha[x + y * M_IMGDATA->m_width] = (unsigned char)(sum_a / blurArea);
+ }
+ }
+
+ return ret_image;
+}
+
+// Blur in the vertical direction
+wxImage wxImage::BlurVertical(int blurRadius) const
+{
+ wxImage ret_image(MakeEmptyClone());
+
+ wxCHECK( ret_image.IsOk(), ret_image );
+
+ const unsigned char* src_data = M_IMGDATA->m_data;
+ unsigned char* dst_data = ret_image.GetData();
+ const unsigned char* src_alpha = M_IMGDATA->m_alpha;
+ unsigned char* dst_alpha = ret_image.GetAlpha();
+
+ // number of pixels we average over
+ const int blurArea = blurRadius*2 + 1;
+
+ // Vertical blurring algorithm - same as horizontal but switched the
+ // opposite direction
+ for ( int x = 0; x < M_IMGDATA->m_width; x++ )
+ {
+ // Variables used in the blurring algorithm
+ long sum_r = 0,
+ sum_g = 0,
+ sum_b = 0,
+ sum_a = 0;
+
+ long pixel_idx;
+ const unsigned char *src;
+ unsigned char *dst;
+
+ // Calculate the average of all pixels in our blur radius box for the
+ // first pixel of the column
+ for ( int kernel_y = -blurRadius; kernel_y <= blurRadius; kernel_y++ )
+ {
+ // To deal with the pixels at the start of a column so it's not
+ // grabbing GOK values from memory at negative indices of the
+ // image's data or grabbing from the previous column
+ if ( kernel_y < 0 )
+ pixel_idx = x;
+ else
+ pixel_idx = x + kernel_y * M_IMGDATA->m_width;
+
+ src = src_data + pixel_idx*3;
+ sum_r += src[0];
+ sum_g += src[1];
+ sum_b += src[2];
+ if ( src_alpha )
+ sum_a += src_alpha[pixel_idx];
+ }
+
+ dst = dst_data + x*3;
+ dst[0] = (unsigned char)(sum_r / blurArea);
+ dst[1] = (unsigned char)(sum_g / blurArea);
+ dst[2] = (unsigned char)(sum_b / blurArea);
+ if ( src_alpha )
+ dst_alpha[x] = (unsigned char)(sum_a / blurArea);
+
+ // Now average the values of the rest of the pixels by just moving the
+ // box along the column from top to bottom
+ for ( int y = 1; y < M_IMGDATA->m_height; y++ )
+ {
+ // Take care of pixels that would be beyond the top edge by
+ // duplicating the top edge pixel for the column
+ if ( y - blurRadius - 1 < 0 )
+ pixel_idx = x;
+ else
+ pixel_idx = x + (y - blurRadius - 1) * M_IMGDATA->m_width;
+
+ // Subtract the value of the pixel at the top of our blur radius box
+ src = src_data + pixel_idx*3;
+ sum_r -= src[0];
+ sum_g -= src[1];
+ sum_b -= src[2];
+ if ( src_alpha )
+ sum_a -= src_alpha[pixel_idx];
+
+ // Take care of the pixels that would be beyond the bottom edge of
+ // the image similar to the top edge
+ if ( y + blurRadius > M_IMGDATA->m_height - 1 )
+ pixel_idx = x + (M_IMGDATA->m_height - 1) * M_IMGDATA->m_width;
+ else
+ pixel_idx = x + (blurRadius + y) * M_IMGDATA->m_width;
+
+ // Add the value of the pixel being added to the end of our box
+ src = src_data + pixel_idx*3;
+ sum_r += src[0];
+ sum_g += src[1];
+ sum_b += src[2];
+ if ( src_alpha )
+ sum_a += src_alpha[pixel_idx];
+
+ // Save off the averaged data
+ dst = dst_data + (x + y * M_IMGDATA->m_width) * 3;
+ dst[0] = (unsigned char)(sum_r / blurArea);
+ dst[1] = (unsigned char)(sum_g / blurArea);
+ dst[2] = (unsigned char)(sum_b / blurArea);
+ if ( src_alpha )
+ dst_alpha[x + y * M_IMGDATA->m_width] = (unsigned char)(sum_a / blurArea);
+ }
+ }
+
+ return ret_image;
+}
+
+// The new blur function
+wxImage wxImage::Blur(int blurRadius) const
+{
+ wxImage ret_image;
+ ret_image.Create(M_IMGDATA->m_width, M_IMGDATA->m_height, false);
+
+ // Blur the image in each direction
+ ret_image = BlurHorizontal(blurRadius);
+ ret_image = ret_image.BlurVertical(blurRadius);
+
+ return ret_image;
+}
+
+wxImage wxImage::Rotate90( bool clockwise ) const
+{
+ wxImage image(MakeEmptyClone(Clone_SwapOrientation));
+
+ wxCHECK( image.IsOk(), image );
+
+ long height = M_IMGDATA->m_height;
+ long width = M_IMGDATA->m_width;
+
+ if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_X) )
+ {
+ int hot_x = GetOptionInt( wxIMAGE_OPTION_CUR_HOTSPOT_X );
+ image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y,
+ clockwise ? hot_x : width - 1 - hot_x);
+ }
+
+ if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y) )
+ {
+ int hot_y = GetOptionInt( wxIMAGE_OPTION_CUR_HOTSPOT_Y );
+ image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X,
+ clockwise ? height - 1 - hot_y : hot_y);
+ }
+
+ unsigned char *data = image.GetData();
+ unsigned char *target_data;
+
+ // we rotate the image in 21-pixel (63-byte) wide strips
+ // to make better use of cpu cache - memory transfers
+ // (note: while much better than single-pixel "strips",
+ // our vertical strips will still generally straddle 64-byte cachelines)
+ for (long ii = 0; ii < width; )
+ {
+ long next_ii = wxMin(ii + 21, width);
+
+ for (long j = 0; j < height; j++)
+ {
+ const unsigned char *source_data
+ = M_IMGDATA->m_data + (j*width + ii)*3;
+
+ for (long i = ii; i < next_ii; i++)
+ {
+ if ( clockwise )
+ {
+ target_data = data + ((i + 1)*height - j - 1)*3;
+ }
+ else
+ {
+ target_data = data + (height*(width - 1 - i) + j)*3;
+ }
+ memcpy( target_data, source_data, 3 );
+ source_data += 3;
+ }
+ }
+
+ ii = next_ii;
+ }
+
+ const unsigned char *source_alpha = M_IMGDATA->m_alpha;
+
+ if ( source_alpha )
+ {
+ unsigned char *alpha_data = image.GetAlpha();
+ unsigned char *target_alpha = 0 ;
+
+ for (long ii = 0; ii < width; )
+ {
+ long next_ii = wxMin(ii + 64, width);
+
+ for (long j = 0; j < height; j++)
+ {
+ source_alpha = M_IMGDATA->m_alpha + j*width + ii;
+
+ for (long i = ii; i < next_ii; i++)
+ {
+ if ( clockwise )
+ {
+ target_alpha = alpha_data + (i+1)*height - j - 1;
+ }
+ else
+ {
+ target_alpha = alpha_data + height*(width - i - 1) + j;
+ }
+
+ *target_alpha = *source_alpha++;
+ }
+ }
+
+ ii = next_ii;
+ }
+ }
+
+ return image;
+}
+
+wxImage wxImage::Rotate180() const
+{
+ wxImage image(MakeEmptyClone());
+
+ wxCHECK( image.IsOk(), image );
+
+ long height = M_IMGDATA->m_height;
+ long width = M_IMGDATA->m_width;
+
+ if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_X) )
+ {
+ image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X,
+ width - 1 - GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X));
+ }
+
+ if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y) )
+ {
+ image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y,
+ height - 1 - GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_Y));
+ }
+
+ unsigned char *data = image.GetData();
+ unsigned char *alpha = image.GetAlpha();
+ const unsigned char *source_data = M_IMGDATA->m_data;
+ unsigned char *target_data = data + width * height * 3;
+
+ for (long j = 0; j < height; j++)
+ {
+ for (long i = 0; i < width; i++)
+ {
+ target_data -= 3;
+ memcpy( target_data, source_data, 3 );
+ source_data += 3;
+ }
+ }
+
+ if ( alpha )
+ {
+ const unsigned char *src_alpha = M_IMGDATA->m_alpha;
+ unsigned char *dest_alpha = alpha + width * height;
+
+ for (long j = 0; j < height; ++j)
+ {
+ for (long i = 0; i < width; ++i)
+ {
+ *(--dest_alpha) = *(src_alpha++);
+ }
+ }
+ }
+
+ return image;
+}
+
+wxImage wxImage::Mirror( bool horizontally ) const
+{
+ wxImage image(MakeEmptyClone());
+
+ wxCHECK( image.IsOk(), image );
+
+ long height = M_IMGDATA->m_height;
+ long width = M_IMGDATA->m_width;
+
+ unsigned char *data = image.GetData();
+ unsigned char *alpha = image.GetAlpha();
+ const unsigned char *source_data = M_IMGDATA->m_data;
+ unsigned char *target_data;
+
+ if (horizontally)
+ {
+ for (long j = 0; j < height; j++)
+ {
+ data += width*3;
+ target_data = data-3;
+ for (long i = 0; i < width; i++)
+ {
+ memcpy( target_data, source_data, 3 );
+ source_data += 3;
+ target_data -= 3;
+ }
+ }
+
+ if (alpha != NULL)
+ {
+ // src_alpha starts at the first pixel and increases by 1 after each step
+ // (a step here is the copy of the alpha value of one pixel)
+ const unsigned char *src_alpha = M_IMGDATA->m_alpha;
+ // dest_alpha starts just beyond the first line, decreases before each step,
+ // and after each line is finished, increases by 2 widths (skipping the line
+ // just copied and the line that will be copied next)
+ unsigned char *dest_alpha = alpha + width;
+
+ for (long jj = 0; jj < height; ++jj)
+ {
+ for (long i = 0; i < width; ++i) {
+ *(--dest_alpha) = *(src_alpha++); // copy one pixel
+ }
+ dest_alpha += 2 * width; // advance beyond the end of the next line
+ }
+ }
+ }
+ else
+ {
+ for (long i = 0; i < height; i++)
+ {
+ target_data = data + 3*width*(height-1-i);
+ memcpy( target_data, source_data, (size_t)3*width );
+ source_data += 3*width;
+ }
+
+ if ( alpha )
+ {
+ // src_alpha starts at the first pixel and increases by 1 width after each step
+ // (a step here is the copy of the alpha channel of an entire line)
+ const unsigned char *src_alpha = M_IMGDATA->m_alpha;
+ // dest_alpha starts just beyond the last line (beyond the whole image)
+ // and decreases by 1 width before each step
+ unsigned char *dest_alpha = alpha + width * height;
+
+ for (long jj = 0; jj < height; ++jj)
+ {
+ dest_alpha -= width;
+ memcpy( dest_alpha, src_alpha, (size_t)width );
+ src_alpha += width;
+ }
+ }
+ }
+
+ return image;
+}
+
+wxImage wxImage::GetSubImage( const wxRect &rect ) const
+{
+ wxImage image;
+
+ wxCHECK_MSG( IsOk(), image, wxT("invalid image") );
+
+ wxCHECK_MSG( (rect.GetLeft()>=0) && (rect.GetTop()>=0) &&
+ (rect.GetRight()<=GetWidth()) && (rect.GetBottom()<=GetHeight()),
+ image, wxT("invalid subimage size") );
+
+ const int subwidth = rect.GetWidth();
+ const int subheight = rect.GetHeight();
+
+ image.Create( subwidth, subheight, false );
+
+ const unsigned char *src_data = GetData();
+ const unsigned char *src_alpha = M_IMGDATA->m_alpha;
+ unsigned char *subdata = image.GetData();
+ unsigned char *subalpha = NULL;
+
+ wxCHECK_MSG( subdata, image, wxT("unable to create image") );
+
+ if ( src_alpha ) {
+ image.SetAlpha();
+ subalpha = image.GetAlpha();
+ wxCHECK_MSG( subalpha, image, wxT("unable to create alpha channel"));
+ }
+
+ if (M_IMGDATA->m_hasMask)
+ image.SetMaskColour( M_IMGDATA->m_maskRed, M_IMGDATA->m_maskGreen, M_IMGDATA->m_maskBlue );
+
+ const int width = GetWidth();
+ const int pixsoff = rect.GetLeft() + width * rect.GetTop();
+
+ src_data += 3 * pixsoff;
+ src_alpha += pixsoff; // won't be used if was NULL, so this is ok
+
+ for (long j = 0; j < subheight; ++j)
+ {
+ memcpy( subdata, src_data, 3 * subwidth );
+ subdata += 3 * subwidth;
+ src_data += 3 * width;
+ if (subalpha != NULL) {
+ memcpy( subalpha, src_alpha, subwidth );
+ subalpha += subwidth;
+ src_alpha += width;
+ }
+ }
+
+ return image;
+}
+
+wxImage wxImage::Size( const wxSize& size, const wxPoint& pos,
+ int r_, int g_, int b_ ) const
+{
+ wxImage image;
+
+ wxCHECK_MSG( IsOk(), image, wxT("invalid image") );
+ wxCHECK_MSG( (size.GetWidth() > 0) && (size.GetHeight() > 0), image, wxT("invalid size") );
+
+ int width = GetWidth(), height = GetHeight();
+ image.Create(size.GetWidth(), size.GetHeight(), false);
+
+ unsigned char r = (unsigned char)r_;
+ unsigned char g = (unsigned char)g_;
+ unsigned char b = (unsigned char)b_;
+ if ((r_ == -1) && (g_ == -1) && (b_ == -1))
+ {
+ GetOrFindMaskColour( &r, &g, &b );
+ image.SetMaskColour(r, g, b);
+ }
+
+ image.SetRGB(wxRect(), r, g, b);
+
+ // we have two coordinate systems:
+ // source: starting at 0,0 of source image
+ // destination starting at 0,0 of destination image
+ // Documentation says:
+ // "The image is pasted into a new image [...] at the position pos relative
+ // to the upper left of the new image." this means the transition rule is:
+ // "dest coord" = "source coord" + pos;
+
+ // calculate the intersection using source coordinates:
+ wxRect srcRect(0, 0, width, height);
+ wxRect dstRect(-pos, size);
+
+ srcRect.Intersect(dstRect);
+
+ if (!srcRect.IsEmpty())
+ {
+ // insertion point is needed in destination coordinates.
+ // NB: it is not always "pos"!
+ wxPoint ptInsert = srcRect.GetTopLeft() + pos;
+
+ if ((srcRect.GetWidth() == width) && (srcRect.GetHeight() == height))
+ image.Paste(*this, ptInsert.x, ptInsert.y);
+ else
+ image.Paste(GetSubImage(srcRect), ptInsert.x, ptInsert.y);
+ }
+
+ return image;
+}
+
+void wxImage::Paste( const wxImage &image, int x, int y )
+{
+ wxCHECK_RET( IsOk(), wxT("invalid image") );
+ wxCHECK_RET( image.IsOk(), wxT("invalid image") );
+
+ AllocExclusive();
+
+ int xx = 0;
+ int yy = 0;
+ int width = image.GetWidth();
+ int height = image.GetHeight();
+
+ if (x < 0)
+ {
+ xx = -x;
+ width += x;
+ }
+ if (y < 0)
+ {
+ yy = -y;
+ height += y;
+ }
+
+ if ((x+xx)+width > M_IMGDATA->m_width)
+ width = M_IMGDATA->m_width - (x+xx);
+ if ((y+yy)+height > M_IMGDATA->m_height)
+ height = M_IMGDATA->m_height - (y+yy);
+
+ if (width < 1) return;
+ if (height < 1) return;
+
+ // If we can, copy the data using memcpy() as this is the fastest way. But
+ // for this the image being pasted must have "compatible" mask with this
+ // one meaning that either it must not have one at all or it must use the
+ // same masked colour.
+ if ( !image.HasMask() ||
+ ((HasMask() &&
+ (GetMaskRed()==image.GetMaskRed()) &&
+ (GetMaskGreen()==image.GetMaskGreen()) &&
+ (GetMaskBlue()==image.GetMaskBlue()))) )
+ {
+ const unsigned char* source_data = image.GetData() + 3*(xx + yy*image.GetWidth());
+ int source_step = image.GetWidth()*3;
+
+ unsigned char* target_data = GetData() + 3*((x+xx) + (y+yy)*M_IMGDATA->m_width);
+ int target_step = M_IMGDATA->m_width*3;
+ for (int j = 0; j < height; j++)
+ {
+ memcpy( target_data, source_data, width*3 );
+ source_data += source_step;
+ target_data += target_step;
+ }
+ }
+
+ // Copy over the alpha channel from the original image
+ if ( image.HasAlpha() )
+ {
+ if ( !HasAlpha() )
+ InitAlpha();
+
+ const unsigned char* source_data = image.GetAlpha() + xx + yy*image.GetWidth();
+ int source_step = image.GetWidth();
+
+ unsigned char* target_data = GetAlpha() + (x+xx) + (y+yy)*M_IMGDATA->m_width;
+ int target_step = M_IMGDATA->m_width;
+
+ for (int j = 0; j < height; j++,
+ source_data += source_step,
+ target_data += target_step)
+ {
+ memcpy( target_data, source_data, width );
+ }
+ }
+
+ if (!HasMask() && image.HasMask())
+ {
+ unsigned char r = image.GetMaskRed();
+ unsigned char g = image.GetMaskGreen();
+ unsigned char b = image.GetMaskBlue();
+
+ const unsigned char* source_data = image.GetData() + 3*(xx + yy*image.GetWidth());
+ int source_step = image.GetWidth()*3;
+
+ unsigned char* target_data = GetData() + 3*((x+xx) + (y+yy)*M_IMGDATA->m_width);