forked from KolibriOS/kolibrios
364 lines
6.8 KiB
C
364 lines
6.8 KiB
C
/*
|
|
* We draw a triangle with various interpolations
|
|
*/
|
|
|
|
{
|
|
ZBufferPoint *t,*pr1,*pr2,*l1,*l2;
|
|
float fdx1, fdx2, fdy1, fdy2, fz, d1, d2;
|
|
unsigned short *pz1;
|
|
PIXEL *pp1;
|
|
int part,update_left,update_right;
|
|
|
|
int nb_lines,dx1,dy1,tmp,dx2,dy2;
|
|
|
|
int error,derror;
|
|
int x1,dxdy_min,dxdy_max;
|
|
/* warning: x2 is multiplied by 2^16 */
|
|
int x2,dx2dy2;
|
|
|
|
#ifdef INTERP_Z
|
|
int z1,dzdx,dzdy,dzdl_min,dzdl_max;
|
|
#endif
|
|
#ifdef INTERP_RGB
|
|
int r1,drdx,drdy,drdl_min,drdl_max;
|
|
int g1,dgdx,dgdy,dgdl_min,dgdl_max;
|
|
int b1,dbdx,dbdy,dbdl_min,dbdl_max;
|
|
#endif
|
|
#ifdef INTERP_ST
|
|
int s1,dsdx,dsdy,dsdl_min,dsdl_max;
|
|
int t1,dtdx,dtdy,dtdl_min,dtdl_max;
|
|
#endif
|
|
#ifdef INTERP_STZ
|
|
float sz1,dszdx,dszdy,dszdl_min,dszdl_max;
|
|
float tz1,dtzdx,dtzdy,dtzdl_min,dtzdl_max;
|
|
#endif
|
|
|
|
/* we sort the vertex with increasing y */
|
|
if (p1->y < p0->y) {
|
|
t = p0;
|
|
p0 = p1;
|
|
p1 = t;
|
|
}
|
|
if (p2->y < p0->y) {
|
|
t = p2;
|
|
p2 = p1;
|
|
p1 = p0;
|
|
p0 = t;
|
|
} else if (p2->y < p1->y) {
|
|
t = p1;
|
|
p1 = p2;
|
|
p2 = t;
|
|
}
|
|
|
|
/* we compute dXdx and dXdy for all interpolated values */
|
|
|
|
fdx1 = p1->x - p0->x;
|
|
fdy1 = p1->y - p0->y;
|
|
|
|
fdx2 = p2->x - p0->x;
|
|
fdy2 = p2->y - p0->y;
|
|
|
|
fz = fdx1 * fdy2 - fdx2 * fdy1;
|
|
if (fz == 0)
|
|
return;
|
|
fz = 1.0 / fz;
|
|
|
|
fdx1 *= fz;
|
|
fdy1 *= fz;
|
|
fdx2 *= fz;
|
|
fdy2 *= fz;
|
|
|
|
#ifdef INTERP_Z
|
|
d1 = p1->z - p0->z;
|
|
d2 = p2->z - p0->z;
|
|
dzdx = (int) (fdy2 * d1 - fdy1 * d2);
|
|
dzdy = (int) (fdx1 * d2 - fdx2 * d1);
|
|
#endif
|
|
|
|
#ifdef INTERP_RGB
|
|
d1 = p1->r - p0->r;
|
|
d2 = p2->r - p0->r;
|
|
drdx = (int) (fdy2 * d1 - fdy1 * d2);
|
|
drdy = (int) (fdx1 * d2 - fdx2 * d1);
|
|
|
|
d1 = p1->g - p0->g;
|
|
d2 = p2->g - p0->g;
|
|
dgdx = (int) (fdy2 * d1 - fdy1 * d2);
|
|
dgdy = (int) (fdx1 * d2 - fdx2 * d1);
|
|
|
|
d1 = p1->b - p0->b;
|
|
d2 = p2->b - p0->b;
|
|
dbdx = (int) (fdy2 * d1 - fdy1 * d2);
|
|
dbdy = (int) (fdx1 * d2 - fdx2 * d1);
|
|
|
|
#endif
|
|
|
|
#ifdef INTERP_ST
|
|
d1 = p1->s - p0->s;
|
|
d2 = p2->s - p0->s;
|
|
dsdx = (int) (fdy2 * d1 - fdy1 * d2);
|
|
dsdy = (int) (fdx1 * d2 - fdx2 * d1);
|
|
|
|
d1 = p1->t - p0->t;
|
|
d2 = p2->t - p0->t;
|
|
dtdx = (int) (fdy2 * d1 - fdy1 * d2);
|
|
dtdy = (int) (fdx1 * d2 - fdx2 * d1);
|
|
#endif
|
|
|
|
#ifdef INTERP_STZ
|
|
{
|
|
float zz;
|
|
zz=(float) p0->z;
|
|
p0->sz= (float) p0->s * zz;
|
|
p0->tz= (float) p0->t * zz;
|
|
zz=(float) p1->z;
|
|
p1->sz= (float) p1->s * zz;
|
|
p1->tz= (float) p1->t * zz;
|
|
zz=(float) p2->z;
|
|
p2->sz= (float) p2->s * zz;
|
|
p2->tz= (float) p2->t * zz;
|
|
|
|
d1 = p1->sz - p0->sz;
|
|
d2 = p2->sz - p0->sz;
|
|
dszdx = (fdy2 * d1 - fdy1 * d2);
|
|
dszdy = (fdx1 * d2 - fdx2 * d1);
|
|
|
|
d1 = p1->tz - p0->tz;
|
|
d2 = p2->tz - p0->tz;
|
|
dtzdx = (fdy2 * d1 - fdy1 * d2);
|
|
dtzdy = (fdx1 * d2 - fdx2 * d1);
|
|
}
|
|
#endif
|
|
|
|
/* screen coordinates */
|
|
|
|
pp1 = (PIXEL *) ((char *) zb->pbuf + zb->linesize * p0->y);
|
|
pz1 = zb->zbuf + p0->y * zb->xsize;
|
|
|
|
DRAW_INIT();
|
|
|
|
for(part=0;part<2;part++) {
|
|
if (part == 0) {
|
|
if (fz > 0) {
|
|
update_left=1;
|
|
update_right=1;
|
|
l1=p0;
|
|
l2=p2;
|
|
pr1=p0;
|
|
pr2=p1;
|
|
} else {
|
|
update_left=1;
|
|
update_right=1;
|
|
l1=p0;
|
|
l2=p1;
|
|
pr1=p0;
|
|
pr2=p2;
|
|
}
|
|
nb_lines = p1->y - p0->y;
|
|
} else {
|
|
/* second part */
|
|
if (fz > 0) {
|
|
update_left=0;
|
|
update_right=1;
|
|
pr1=p1;
|
|
pr2=p2;
|
|
} else {
|
|
update_left=1;
|
|
update_right=0;
|
|
l1=p1;
|
|
l2=p2;
|
|
}
|
|
nb_lines = p2->y - p1->y + 1;
|
|
}
|
|
|
|
/* compute the values for the left edge */
|
|
|
|
if (update_left) {
|
|
dy1 = l2->y - l1->y;
|
|
dx1 = l2->x - l1->x;
|
|
if (dy1 > 0)
|
|
tmp = (dx1 << 16) / dy1;
|
|
else
|
|
tmp = 0;
|
|
x1 = l1->x;
|
|
error = 0;
|
|
derror = tmp & 0x0000ffff;
|
|
dxdy_min = tmp >> 16;
|
|
dxdy_max = dxdy_min + 1;
|
|
|
|
#ifdef INTERP_Z
|
|
z1=l1->z;
|
|
dzdl_min=(dzdy + dzdx * dxdy_min);
|
|
dzdl_max=dzdl_min + dzdx;
|
|
#endif
|
|
#ifdef INTERP_RGB
|
|
r1=l1->r;
|
|
drdl_min=(drdy + drdx * dxdy_min);
|
|
drdl_max=drdl_min + drdx;
|
|
|
|
g1=l1->g;
|
|
dgdl_min=(dgdy + dgdx * dxdy_min);
|
|
dgdl_max=dgdl_min + dgdx;
|
|
|
|
b1=l1->b;
|
|
dbdl_min=(dbdy + dbdx * dxdy_min);
|
|
dbdl_max=dbdl_min + dbdx;
|
|
#endif
|
|
#ifdef INTERP_ST
|
|
s1=l1->s;
|
|
dsdl_min=(dsdy + dsdx * dxdy_min);
|
|
dsdl_max=dsdl_min + dsdx;
|
|
|
|
t1=l1->t;
|
|
dtdl_min=(dtdy + dtdx * dxdy_min);
|
|
dtdl_max=dtdl_min + dtdx;
|
|
#endif
|
|
#ifdef INTERP_STZ
|
|
sz1=l1->sz;
|
|
dszdl_min=(dszdy + dszdx * dxdy_min);
|
|
dszdl_max=dszdl_min + dszdx;
|
|
|
|
tz1=l1->tz;
|
|
dtzdl_min=(dtzdy + dtzdx * dxdy_min);
|
|
dtzdl_max=dtzdl_min + dtzdx;
|
|
#endif
|
|
}
|
|
|
|
/* compute values for the right edge */
|
|
|
|
if (update_right) {
|
|
dx2 = (pr2->x - pr1->x);
|
|
dy2 = (pr2->y - pr1->y);
|
|
if (dy2>0)
|
|
dx2dy2 = ( dx2 << 16) / dy2;
|
|
else
|
|
dx2dy2 = 0;
|
|
x2 = pr1->x << 16;
|
|
}
|
|
|
|
/* we draw all the scan line of the part */
|
|
|
|
while (nb_lines>0) {
|
|
nb_lines--;
|
|
#ifndef DRAW_LINE
|
|
/* generic draw line */
|
|
{
|
|
register PIXEL *pp;
|
|
register int n;
|
|
#ifdef INTERP_Z
|
|
register unsigned short *pz;
|
|
register unsigned int z,zz;
|
|
#endif
|
|
#ifdef INTERP_RGB
|
|
register unsigned int or1,og1,ob1;
|
|
#endif
|
|
#ifdef INTERP_ST
|
|
register unsigned int s,t;
|
|
#endif
|
|
#ifdef INTERP_STZ
|
|
float sz,tz;
|
|
#endif
|
|
|
|
n=(x2 >> 16) - x1;
|
|
pp=(PIXEL *)((char *)pp1 + x1 * PSZB);
|
|
#ifdef INTERP_Z
|
|
pz=pz1+x1;
|
|
z=z1;
|
|
#endif
|
|
#ifdef INTERP_RGB
|
|
or1 = r1;
|
|
og1 = g1;
|
|
ob1 = b1;
|
|
#endif
|
|
#ifdef INTERP_ST
|
|
s=s1;
|
|
t=t1;
|
|
#endif
|
|
#ifdef INTERP_STZ
|
|
sz=sz1;
|
|
tz=tz1;
|
|
#endif
|
|
while (n>=3) {
|
|
PUT_PIXEL(0);
|
|
PUT_PIXEL(1);
|
|
PUT_PIXEL(2);
|
|
PUT_PIXEL(3);
|
|
#ifdef INTERP_Z
|
|
pz+=4;
|
|
#endif
|
|
pp=(PIXEL *)((char *)pp + 4 * PSZB);
|
|
n-=4;
|
|
}
|
|
while (n>=0) {
|
|
PUT_PIXEL(0);
|
|
#ifdef INTERP_Z
|
|
pz+=1;
|
|
#endif
|
|
pp=(PIXEL *)((char *)pp + PSZB);
|
|
n-=1;
|
|
}
|
|
}
|
|
#else
|
|
DRAW_LINE();
|
|
#endif
|
|
|
|
/* left edge */
|
|
error+=derror;
|
|
if (error > 0) {
|
|
error-=0x10000;
|
|
x1+=dxdy_max;
|
|
#ifdef INTERP_Z
|
|
z1+=dzdl_max;
|
|
#endif
|
|
#ifdef INTERP_RGB
|
|
r1+=drdl_max;
|
|
g1+=dgdl_max;
|
|
b1+=dbdl_max;
|
|
#endif
|
|
#ifdef INTERP_ST
|
|
s1+=dsdl_max;
|
|
t1+=dtdl_max;
|
|
#endif
|
|
#ifdef INTERP_STZ
|
|
sz1+=dszdl_max;
|
|
tz1+=dtzdl_max;
|
|
#endif
|
|
} else {
|
|
x1+=dxdy_min;
|
|
#ifdef INTERP_Z
|
|
z1+=dzdl_min;
|
|
#endif
|
|
#ifdef INTERP_RGB
|
|
r1+=drdl_min;
|
|
g1+=dgdl_min;
|
|
b1+=dbdl_min;
|
|
#endif
|
|
#ifdef INTERP_ST
|
|
s1+=dsdl_min;
|
|
t1+=dtdl_min;
|
|
#endif
|
|
#ifdef INTERP_STZ
|
|
sz1+=dszdl_min;
|
|
tz1+=dtzdl_min;
|
|
#endif
|
|
}
|
|
|
|
/* right edge */
|
|
x2+=dx2dy2;
|
|
|
|
/* screen coordinates */
|
|
pp1=(PIXEL *)((char *)pp1 + zb->linesize);
|
|
pz1+=zb->xsize;
|
|
}
|
|
}
|
|
}
|
|
|
|
#undef INTERP_Z
|
|
#undef INTERP_RGB
|
|
#undef INTERP_ST
|
|
#undef INTERP_STZ
|
|
|
|
#undef DRAW_INIT
|
|
#undef DRAW_LINE
|
|
#undef PUT_PIXEL
|