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Copy pathr_triaffine.js
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r_triaffine.js
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//masked and affine could share the same drawtri
//but for now its easier to copy and paste
function drawStripAffine(i, sx, ex, su, sv, cu, cv, sz, cm)
{
var k; var tx; var nk;
nk = ex - sx;
for (k = 0; k < nk; k+=1)
{
if (getDepth(k+sx, i) > sz)
{
tx = getTexel(su, sv); //affine
setPixel(k+sx, i, texData[reti], texData[reti+1], texData[reti+2]);
// setPixel(k+sx, i, texData[reti],0, 0);
setDepth(k+sx, i, sz);
}
sz += cm;
su += cu;
sv += cv;
} //nextk
}//drawstripmask
function drawTriAffine(x0, y0, z0, u0, v0, x1, y1, z1, u1,v1, x2, y2, z2, u2,v2)
{
var sx, ex; var ax, bx; var i, k;
var xst0, xst1, xst2;
var dy0, dy1, dy2;
var sz, ez; var az, bz;
var zst0, zst1, zst2;
var su, eu; var au, bu;
var ust0, ust1, ust2;
var sv, ev; var av, bv;
var vst0, vst1, vst2;
if (y1 < y0) { sx=x1;x1=x0;x0=sx; ex=y1;y1=y0;y0=ex; ex=z1;z1=z0;z0=ex; ex=u1;u1=u0;u0=ex; ex=v1;v1=v0;v0=ex; }
if (y2 < y0) { sx=x2;x2=x0;x0=sx; ex=y2;y2=y0;y0=ex; ex=z2;z2=z0;z0=ex; ex=u2;u2=u0;u0=ex; ex=v2;v2=v0;v0=ex; }
if (y2 < y1) { sx=x2;x2=x1;x1=sx; ex=y2;y2=y1;y1=ex; ex=z2;z2=z1;z1=ex; ex=u2;u2=u1;u1=ex; ex=v2;v2=v1;v1=ex; }
//this hack is still necessary
y0 = (y0-0.5)|0; y2 = (y2+0.5)|0;
dy0 = (y1 - y0); dy1 = (y2 - y1); dy2 = (y0 - y2);
if (dy2 > -2) { return; } //hack -- dont render tris shorter than 2 pixels
xst0 = 0; xst1 = 0; xst2 = 0;
zst0 = 0; zst1 = 0; zst2 = 0;
ust0 = 0; ust1 = 0; ust2 = 0;
vst0 = 0; vst1 = 0; vst2 = 0;
//perspcorrect
/*
u0 *= (1-z0); v0 *= (1-z0);
u1 *= (1-z1); v1 *= (1-z1);
u2 *= (1-z2); v2 *= (1-z2);
*/
if (dy0!=0) { xst0 = (x1 - x0) / dy0; zst0 = (z1 - z0) / dy0; ust0 = (u1 - u0) / dy0; vst0 = (v1 - v0) / dy0; }
if (dy1!=0) { xst1 = (x2 - x1) / dy1; zst1 = (z2 - z1) / dy1; ust1 = (u2 - u1) / dy1; vst1 = (v2 - v1) / dy1; }
if (dy2!=0) { xst2 = (x0 - x2) / dy2; zst2 = (z0 - z2) / dy2; ust2 = (u0 - u2) / dy2; vst2 = (v0 - v2) / dy2; }
ax = x0; bx = x0;
az = z0; bz = z0;
au = u0; bu = u0;
av = v0; bv = v0;
var cu; var cv; var tx; var tz;
var cm;
for (i = y0; i < y1; i+=1)
{
if (ax < bx) { sx = ax; ex = bx; } else { sx = bx; ex = ax; }
if (ax < bx) { sz = az; ez = bz; } else { sz = bz; ez = az; }
if (ax < bx) { su = au; eu = bu; } else { su = bu; eu = au; }
if (ax < bx) { sv = av; ev = bv; } else { sv = bv; ev = av; }
//if ((ex-sx) == 0) { ex+=1; }
cm = (ez - sz) / (ex - sx);
cu = (eu - su) / (ex - sx);
cv = (ev - sv) / (ex - sx);
if (i > y0)
{
if (sx<0){sx=0;} if(ex>320){ex=320;} //fix for hack
}
drawStripAffine(i, sx,ex, su,sv, cu,cv, sz, cm);
ax += xst0; bx += xst2;
az += zst0; bz += zst2;
au += ust0; bu += ust2;
av += vst0; bv += vst2;
}//nexti
ax = x1; az = z1;
au = u1; av = v1;
for (i = y1; i < y2; i+=1)
{
if (ax < bx) { sx = ax; ex = bx; } else { sx = bx; ex = ax; }
if (ax < bx) { sz = az; ez = bz; } else { sz = bz; ez = az; }
if (ax < bx) { su = au; eu = bu; } else { su = bu; eu = au; }
if (ax < bx) { sv = av; ev = bv; } else { sv = bv; ev = av; }
cu = (eu - su) / (ex - sx);
cv = (ev - sv) / (ex - sx);
cm = (ez - sz) / (ex - sx);
if (i>y1)
{
if (sx<0){sx=0;} if(ex>320){ex=320;}
}
drawStripAffine(i, sx,ex, su,sv, cu,cv, sz, cm);
ax += xst1; bx += xst2;
az += zst1; bz += zst2;
au += ust1; bu += ust2;
av += vst1; bv += vst2;
}//nexti
}//drawtrimask