Method _zoomSurfaceY

src/Engine/Zoom.cpp:694–905

* Internal 8-bit Zoomer without smoothing. * Source code originally from SDL_gfx (LGPL) with permission by author. * * Zooms 8bit palette/Y 'src' surface to 'dst' surface. * Assumes src and dst surfaces are of 8-bit depth. * Assumes dst surface was allocated with the correct dimensions. * * @param src The surface to zoom (input). * @param dst The zoomed surface (output). * @param flipx Fl

 * @return 0 for success or -1 for error.
 */
int Zoom::_zoomSurfaceY(SDL_Surface * src, SDL_Surface * dst, int flipx, int flipy)
{
	int x, y;
	static Uint32 *sax, *say;
	Uint32 *csax, *csay;
	int csx, csy;
	Uint8 *sp, *dp, *csp;
	int dgap;
	static bool proclaimed = false;

	if (Options::useHQXFilter)
	{
		static bool initDone = false;

		if (!initDone)
		{
			hqxInit();
			initDone = true;
		}

		// HQX_API void HQX_CALLCONV hq2x_32_rb( uint32_t * src, uint32_t src_rowBytes, uint32_t * dest, uint32_t dest_rowBytes, int width, int height );

		if (dst->w == src->w * 2 && dst->h == src->h * 2)
		{
			hq2x_32_rb((uint32_t*) src->pixels, src->pitch, (uint32_t*) dst->pixels, dst->pitch, src->w, src->h);
			return 0;
		}

		if (dst->w == src->w * 3 && dst->h == src->h * 3)
		{
			hq3x_32_rb((uint32_t*) src->pixels, src->pitch, (uint32_t*) dst->pixels, dst->pitch, src->w, src->h);
			return 0;
		}

		if (dst->w == src->w * 4 && dst->h == src->h * 4)
		{
			hq4x_32_rb((uint32_t*) src->pixels, src->pitch, (uint32_t*) dst->pixels, dst->pitch, src->w, src->h);
			return 0;
		}

	}

	if (Options::useScaleFilter)
	{
		// check the resolution to see which of scale2x, scale3x, etc. we need

		if (dst->w == src->w * 2 && dst->h == src->h *2 && !scale_precondition(2, src->format->BytesPerPixel, src->w, src->h))
		{
			scale(2, dst->pixels, dst->pitch, src->pixels, src->pitch, src->format->BytesPerPixel, src->w, src->h);
			return 0;
		}

		if (dst->w == src->w * 3 && dst->h == src->h *3 && !scale_precondition(3, src->format->BytesPerPixel, src->w, src->h))
		{
			scale(3, dst->pixels, dst->pitch, src->pixels, src->pitch, src->format->BytesPerPixel, src->w, src->h);
			return 0;
		}