Refactoring Rasterizer

git-svn-id: svn://ultimatepp.org/upp/trunk@820 f0d560ea-af0d-0410-9eb7-867de7ffcac7

uppdev/ScanLine/ScanLine.cpp

@@ -0,0 +1,135 @@
+#include "ScanLine.h"
+
+ScanLine And0(const ScanLine& a, const ScanLine& b)
+{
+	ScanLine r;
+	r.len = 0;
+	r.x = b.x;
+	byte aval = 0;
+	int  acount = 0;
+	byte bval = 0;
+	int  ai = 0;
+	int  bi = 0;
+	int  bcount = b.x - a.x;
+	while(bcount) {
+		if(ai >= a.data.GetCount())
+			return r;
+		aval = a.data[ai++];
+		if(aval > 128) {
+			acount = aval - 128;
+			aval = a.data[ai++];
+			int n = min(acount, bcount);
+			acount -= n;
+			bcount -= n;
+		}
+		else
+			bcount--;
+	}
+	while(ai < a.data.GetCount() && bi < b.data.GetCount()) {
+		if(acount == 0) {
+			aval = a.data[ai++];
+			if(aval > 128) {
+				acount = aval - 128;
+				aval = a.data[ai++];
+			}
+		}
+		if(bcount == 0) {
+			bval = b.data[bi++];
+			if(bval > 128) {
+				bcount = bval - 128;
+				bval = b.data[bi++];
+			}
+		}
+		if(acount && bcount) {
+			int l = min(acount, bcount);
+			acount -= l;
+			bcount -= l;
+			r.len += l;
+			while(l) {
+				int n = min(l, 127);
+				r.data.Cat(n + 128);
+				r.data.Cat((aval * bval) >> 7);
+				l -= n;
+			}
+		}
+		else {
+			r.data.Cat((aval * bval) >> 7);
+			r.len++;
+			if(acount) acount--;
+			if(bcount) bcount--;
+		}
+	}
+	return r;
+}
+
+ScanLine And(const ScanLine& a, const ScanLine& b)
+{
+	return a.x < b.x ? And0(a, b) : And0(b, a);
+}
+
+ScanLine Pack(int x, const byte *data, int len)
+{
+	ScanLine r;
+	int i = 0;
+	r.x = x;
+	r.len = 0;
+	while(i < len) {
+		int n = i;
+		byte val = data[i++];
+		while(i < len && data[i] == val)
+			i++;
+		n = i - n;
+		if(n > 1) {
+			r.len += n;
+			while(n) {
+				int q = min(n, 127);
+				r.data.Cat(q + 128);
+				r.data.Cat(val);
+				n -= q;
+			}
+		}
+		else {
+			r.data.Cat(val);
+			r.len++;
+		}
+	}
+	return r;
+}
+
+String ScanLine::ToString() const
+{
+	String s;
+	s << "x = " << x << ", len = " << len << ": ";
+	for(int i = 0; i < data.GetCount(); i++) {
+		byte val = data[i];
+		if(val > 128) {
+			int n = val - 128;
+			val = data[++i];
+			while(n--)
+				s << (int)val << ", ";
+		}
+		else
+			s << (int)val << ", ";
+	}
+	s << "datalen: " << data.GetCount();
+	return s;
+}
+
+void Apply(RGBA *t, int len, const RGBA& color, const ScanLine& s)
+{
+	t += s.x;
+	len -= s.x;
+	int si = 0;
+	while(len >= 0 && si < s.data.GetLength()) {
+		byte val = s.data[si++];
+		if(val > 128) {
+			int n = min(len, val - 128);
+			val = s.data[si++];
+			while(n--)
+				AlphaBlendCover7(*t++, color, val);
+			len -= n;
+		}
+		else
+			AlphaBlendCover7(*t++, color, val);
+	}
+}