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-rw-r--r--3rdparty/tinygl-0.4-ugfx/src/ztriangle.h363
1 files changed, 363 insertions, 0 deletions
diff --git a/3rdparty/tinygl-0.4-ugfx/src/ztriangle.h b/3rdparty/tinygl-0.4-ugfx/src/ztriangle.h
new file mode 100644
index 00000000..b6142642
--- /dev/null
+++ b/3rdparty/tinygl-0.4-ugfx/src/ztriangle.h
@@ -0,0 +1,363 @@
+/*
+ * 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
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