U++ forum: Welcome to the forum

Re: BufferPainter::Fill(Image,...) optimization question [message #53750 is a reply to message #53749]

Mon, 27 April 2020 16:51

Tom1
Messages: 1301
Registered: March 2007

Ultimate Contributor

Hi,

Never mind... after all I managed to get through and found the fillers.

While this is not much, I noticed that the following changes improve BufferPainter::Fill(Image,...) performance by about 5 % for MT and about 13 % for ST on my computer. The changes (centered around adding and handling of 'kind' for SpanSource) follow.

Painter/BufferPainter.h:

struct SpanSource {
	int kind;
	SpanSource(){
		kind = IMAGE_OPAQUE;
	}

	virtual void Get(RGBA *span, int x, int y, unsigned len) = 0;
	virtual ~SpanSource() {}
};

Painter/Fillers.cpp:

void SpanFiller::Render(int val, int len)
{
	if(val == 0) {
		t += len;
		s += len;
		return;
	}
	if(alpha != 256)
		val = alpha * val >> 8;

	if(val == 256) {
		if(ss->kind==IMAGE_OPAQUE) memcpy(t,s,len*sizeof(RGBA));
		else{
			for(int i = 0; i < len; i++) {
				if(s[i].a == 255)
					t[i] = s[i];
				else
					AlphaBlend(t[i], s[i]);
			}
		}
		t += len;
		s += len;
	}
	else {
		const RGBA *e = t + len;
		while(t < e)
			AlphaBlendCover8(*t++, *s++, val);
	}
}

Painter/Image.cpp:

struct PainterImageSpan : SpanSource, PainterImageSpanData {
	LinearInterpolator interpolator;

	PainterImageSpan(const PainterImageSpanData& f)
	:	PainterImageSpanData(f) {
		interpolator.Set(xform);
		kind = image.GetKindNoScan(); // Tom added
	}

This just leaves me wondering why is the improvement so insignificant, no matter there is no longer any comparison and/or blending required. Is there yet another layer of transferring pixels somewhere?

Please review the changes. If they are correct and sensible -- which I'm not sure about -- feel free to merge.

Best regards,

Tom

EDIT: Changed default SpanSource::kind to IMAGE_OPAQUE to boost all kinds of filling. The change introduced a slight improvement over the previous round.

[Updated on: Tue, 28 April 2020 00:48]

Report message to a moderator