if ( old_width == width && old_height == height )
return *this;
- // resample the image using either the nearest neighbourhood, bilinear or
- // bicubic method as specified
- switch ( quality )
+ if (quality == wxIMAGE_QUALITY_HIGH)
{
- case wxIMAGE_QUALITY_BICUBIC:
- case wxIMAGE_QUALITY_BILINEAR:
- // both of these algorithms should be used for up-sampling the
- // image only, when down-sampling always use box averaging for best
- // results
- if ( width < old_width && height < old_height )
- image = ResampleBox(width, height);
- else if ( quality == wxIMAGE_QUALITY_BILINEAR )
- image = ResampleBilinear(width, height);
- else if ( quality == wxIMAGE_QUALITY_BICUBIC )
- image = ResampleBicubic(width, height);
- break;
+ quality = (width < old_width && height < old_height)
+ ? wxIMAGE_QUALITY_BOX_AVERAGE
+ : wxIMAGE_QUALITY_BICUBIC;
+ }
+ // Resample the image using the method as specified.
+ switch ( quality )
+ {
case wxIMAGE_QUALITY_NEAREST:
if ( old_width % width == 0 && old_width >= width &&
old_height % height == 0 && old_height >= height )
image = ResampleNearest(width, height);
break;
+
+ case wxIMAGE_QUALITY_BILINEAR:
+ image = ResampleBilinear(width, height);
+ break;
+
+ case wxIMAGE_QUALITY_BICUBIC:
+ image = ResampleBicubic(width, height);
+ break;
+
+ case wxIMAGE_QUALITY_BOX_AVERAGE:
+ image = ResampleBox(width, height);
+ break;
}
// If the original image has a mask, apply the mask to the new image
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);
- j <= int(src_y + scale_factor_y_2);
+ 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);
- i <= src_x + scale_factor_x_2;
+ 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
}
unsigned char *data = image.GetData();
- const unsigned char *source_data = M_IMGDATA->m_data;
unsigned char *target_data;
- unsigned char *alpha_data = image.GetAlpha();
- const unsigned char *source_alpha = M_IMGDATA->m_alpha;
- unsigned char *target_alpha = 0 ;
- for (long j = 0; j < height; j++)
+ // 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; )
{
- for (long i = 0; i < width; i++)
+ long next_ii = wxMin(ii + 21, width);
+
+ for (long j = 0; j < height; j++)
{
- if (clockwise)
- {
- target_data = data + (((i+1)*height) - j - 1)*3;
- if (source_alpha)
- target_alpha = alpha_data + (((i+1)*height) - j - 1);
- }
- else
+ const unsigned char *source_data
+ = M_IMGDATA->m_data + (j*width + ii)*3;
+
+ for (long i = ii; i < next_ii; i++)
{
- target_data = data + ((height*(width-1)) + j - (i*height))*3;
- if (source_alpha)
- target_alpha = alpha_data + ((height*(width-1)) + j - (i*height));
+ 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;
}
- memcpy( target_data, source_data, 3 );
- source_data += 3;
+ }
+
+ ii = next_ii;
+ }
- if (source_alpha)
+ 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++)
{
- memcpy( target_alpha, source_alpha, 1 );
- source_alpha += 1;
+ 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;
}
}
if (width < 1) return;
if (height < 1) return;
- if ((!HasMask() && !image.HasMask()) ||
- (HasMask() && !image.HasMask()) ||
- ((HasMask() && image.HasMask() &&
+ // 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()))))
+ (GetMaskBlue()==image.GetMaskBlue()))) )
{
const unsigned char* source_data = image.GetData() + 3*(xx + yy*image.GetWidth());
int source_step = image.GetWidth()*3;