void GaussianBlur::boxBlur(IntensityMap &input, IntensityMap &result, double radius, bool tileable) {
for(size_t i = 0; i < input.getWidth() * input.getHeight(); i++) {
result.setValue(i, input.at(i));
}
boxBlurH(result, input, radius, tileable);
boxBlurT(input, result, radius, tileable);
}
/**
* Draws gaussian blur filter.
* Uses code from Mozilla (nsSVGFilters.cpp)
*/
void gaussianBlur(cairo_surface_t* surface, int dx, int dy) {
unsigned char* buffer = cairo_image_surface_get_data(surface);
int stride = cairo_image_surface_get_stride(surface);
int width = cairo_image_surface_get_width(surface);
int height = cairo_image_surface_get_height(surface);
wxRect rect(0, 0, width, height);
// Create temporary buffer
unsigned char* tempBuffer = (unsigned char*) calloc((size_t)(stride * height), 1);
if (tempBuffer == NULL)
return;
if (dx & 1) {
// odd
unsigned char* prediv = setupPredivide(2 * (dx / 2) + 1);
boxBlurH(buffer, tempBuffer, stride, rect, dx / 2, dx / 2, prediv);
boxBlurH(tempBuffer, buffer, stride, rect, dx / 2, dx / 2, prediv);
boxBlurH(buffer, tempBuffer, stride, rect, dx / 2, dx / 2, prediv);
delete[] prediv;
} else {
// even
if (dx == 0) {
memcpy(tempBuffer, buffer, (size_t)(stride * height));
} else {
unsigned char* prediv = setupPredivide(2 * (dx / 2) + 1);
unsigned char* prediv2 = setupPredivide(2 * (dx / 2));
boxBlurH(buffer, tempBuffer, stride, rect, dx / 2, dx / 2 - 1, prediv2);
boxBlurH(tempBuffer, buffer, stride, rect, dx / 2 - 1, dx / 2, prediv2);
boxBlurH(buffer, tempBuffer, stride, rect, dx / 2, dx / 2, prediv);
delete[] prediv;
delete[] prediv2;
}
}
if (dy & 1) {
// odd
unsigned char* prediv = setupPredivide(2 * (dy / 2) + 1);
boxBlurV(tempBuffer, buffer, stride, rect, dy / 2, dy / 2, prediv);
boxBlurV(buffer, tempBuffer, stride, rect, dy / 2, dy / 2, prediv);
boxBlurV(tempBuffer, buffer, stride, rect, dy / 2, dy / 2, prediv);
delete[] prediv;
} else {
// even
if (dy == 0) {
memcpy(buffer, tempBuffer, (size_t)(stride * height));
} else {
unsigned char* prediv = setupPredivide(2 * (dy / 2) + 1);
unsigned char* prediv2 = setupPredivide(2 * (dy / 2));
boxBlurV(tempBuffer, buffer, stride, rect, dy / 2, dy / 2 - 1, prediv2);
boxBlurV(buffer, tempBuffer, stride, rect, dy / 2 - 1, dy / 2, prediv2);
boxBlurV(tempBuffer, buffer, stride, rect, dy / 2, dy / 2, prediv);
delete[] prediv;
delete[] prediv2;
}
}
free(tempBuffer);
}
