ultimatepp/uppdev/ScanLine/ScanLine.cpp
cxl 00580386fa ScanLine rasterizer
git-svn-id: svn://ultimatepp.org/upp/trunk@824 f0d560ea-af0d-0410-9eb7-867de7ffcac7
2009-01-29 11:06:17 +00:00

136 lines
2.5 KiB
C++

#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 << ", right = " << len + x << ": ";
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)
{
RGBA *e = t + len;
const char *q = ~s.data;
const char *qe = s.data.End();
t += s.x;
while(t < e && q < qe) {
byte val = *q++;
if(val > 128) {
RGBA *e1 = min(e, t + val - 128);
val = *q++;
while(t < e1)
AlphaBlendCover7(*t++, color, val);
}
else
AlphaBlendCover7(*t++, color, val);
// DDUMP(t - e);
}
}