aboutsummaryrefslogtreecommitdiffstats
path: root/3rdparty/tinygl-0.4-ugfx/src/ztriangle.c
diff options
context:
space:
mode:
Diffstat (limited to '3rdparty/tinygl-0.4-ugfx/src/ztriangle.c')
-rw-r--r--3rdparty/tinygl-0.4-ugfx/src/ztriangle.c394
1 files changed, 394 insertions, 0 deletions
diff --git a/3rdparty/tinygl-0.4-ugfx/src/ztriangle.c b/3rdparty/tinygl-0.4-ugfx/src/ztriangle.c
new file mode 100644
index 00000000..366d75c5
--- /dev/null
+++ b/3rdparty/tinygl-0.4-ugfx/src/ztriangle.c
@@ -0,0 +1,394 @@
+#include <stdlib.h>
+#include "zbuffer.h"
+
+#define ZCMP(z,zpix) ((z) >= (zpix))
+
+void ZB_fillTriangleFlat(ZBuffer *zb,
+ ZBufferPoint *p0,ZBufferPoint *p1,ZBufferPoint *p2)
+{
+#if TGL_FEATURE_RENDER_BITS == 24
+ unsigned char colorR, colorG, colorB;
+#else
+ int color;
+#endif
+
+#define INTERP_Z
+
+#if TGL_FEATURE_RENDER_BITS == 24
+
+#define DRAW_INIT() \
+{ \
+ colorR=p2->r>>8; \
+ colorG=p2->g>>8; \
+ colorB=p2->b>>8; \
+}
+
+#define PUT_PIXEL(_a) \
+{ \
+ zz=z >> ZB_POINT_Z_FRAC_BITS; \
+ if (ZCMP(zz,pz[_a])) { \
+ pp[3 * _a]=colorR;\
+ pp[3 * _a + 1]=colorG;\
+ pp[3 * _a + 2]=colorB;\
+ pz[_a]=zz; \
+ }\
+ z+=dzdx; \
+}
+
+#else
+
+#define DRAW_INIT() \
+{ \
+ color=RGB_TO_PIXEL(p2->r,p2->g,p2->b); \
+}
+
+#define PUT_PIXEL(_a) \
+{ \
+ zz=z >> ZB_POINT_Z_FRAC_BITS; \
+ if (ZCMP(zz,pz[_a])) { \
+ pp[_a]=color; \
+ pz[_a]=zz; \
+ } \
+ z+=dzdx; \
+}
+#endif /* TGL_FEATURE_RENDER_BITS == 24 */
+
+#include "ztriangle.h"
+}
+
+/*
+ * Smooth filled triangle.
+ * The code below is very tricky :)
+ */
+
+void ZB_fillTriangleSmooth(ZBuffer *zb,
+ ZBufferPoint *p0,ZBufferPoint *p1,ZBufferPoint *p2)
+{
+#if TGL_FEATURE_RENDER_BITS == 16
+ int _drgbdx;
+#endif
+
+#define INTERP_Z
+#define INTERP_RGB
+
+#define SAR_RND_TO_ZERO(v,n) (v / (1<<n))
+
+#if TGL_FEATURE_RENDER_BITS == 24
+
+#define DRAW_INIT() \
+{ \
+}
+
+#define PUT_PIXEL(_a) \
+{ \
+ zz=z >> ZB_POINT_Z_FRAC_BITS; \
+ if (ZCMP(zz,pz[_a])) { \
+ pp[3 * _a]=or1 >> 8;\
+ pp[3 * _a + 1]=og1 >> 8;\
+ pp[3 * _a + 2]=ob1 >> 8;\
+ pz[_a]=zz; \
+ }\
+ z+=dzdx; \
+ og1+=dgdx; \
+ or1+=drdx; \
+ ob1+=dbdx; \
+}
+
+#elif TGL_FEATURE_RENDER_BITS == 16
+
+#define DRAW_INIT() \
+{ \
+ _drgbdx=(SAR_RND_TO_ZERO(drdx,6) << 22) & 0xFFC00000; \
+ _drgbdx|=SAR_RND_TO_ZERO(dgdx,5) & 0x000007FF; \
+ _drgbdx|=(SAR_RND_TO_ZERO(dbdx,7) << 12) & 0x001FF000; \
+}
+
+
+#define PUT_PIXEL(_a) \
+{ \
+ zz=z >> ZB_POINT_Z_FRAC_BITS; \
+ if (ZCMP(zz,pz[_a])) { \
+ tmp=rgb & 0xF81F07E0; \
+ pp[_a]=tmp | (tmp >> 16); \
+ pz[_a]=zz; \
+ } \
+ z+=dzdx; \
+ rgb=(rgb+drgbdx) & ( ~ 0x00200800); \
+}
+
+#define DRAW_LINE() \
+{ \
+ register unsigned short *pz; \
+ register PIXEL *pp; \
+ register unsigned int tmp,z,zz,rgb,drgbdx; \
+ register int n; \
+ n=(x2 >> 16) - x1; \
+ pp=pp1+x1; \
+ pz=pz1+x1; \
+ z=z1; \
+ rgb=(r1 << 16) & 0xFFC00000; \
+ rgb|=(g1 >> 5) & 0x000007FF; \
+ rgb|=(b1 << 5) & 0x001FF000; \
+ drgbdx=_drgbdx; \
+ while (n>=3) { \
+ PUT_PIXEL(0); \
+ PUT_PIXEL(1); \
+ PUT_PIXEL(2); \
+ PUT_PIXEL(3); \
+ pz+=4; \
+ pp+=4; \
+ n-=4; \
+ } \
+ while (n>=0) { \
+ PUT_PIXEL(0); \
+ pz+=1; \
+ pp+=1; \
+ n-=1; \
+ } \
+}
+
+#else
+
+#define DRAW_INIT() \
+{ \
+}
+
+#define PUT_PIXEL(_a) \
+{ \
+ zz=z >> ZB_POINT_Z_FRAC_BITS; \
+ if (ZCMP(zz,pz[_a])) { \
+ pp[_a] = RGB_TO_PIXEL(or1, og1, ob1);\
+ pz[_a]=zz; \
+ }\
+ z+=dzdx; \
+ og1+=dgdx; \
+ or1+=drdx; \
+ ob1+=dbdx; \
+}
+
+#endif /* TGL_FEATURE_RENDER_BITS */
+
+#include "ztriangle.h"
+}
+
+void ZB_setTexture(ZBuffer *zb,PIXEL *texture)
+{
+ zb->current_texture=texture;
+}
+
+void ZB_fillTriangleMapping(ZBuffer *zb,
+ ZBufferPoint *p0,ZBufferPoint *p1,ZBufferPoint *p2)
+{
+ PIXEL *texture;
+
+#define INTERP_Z
+#define INTERP_ST
+
+#define DRAW_INIT() \
+{ \
+ texture=zb->current_texture; \
+}
+
+#if TGL_FEATURE_RENDER_BITS == 24
+
+#define PUT_PIXEL(_a) \
+{ \
+ unsigned char *ptr;\
+ zz=z >> ZB_POINT_Z_FRAC_BITS; \
+ if (ZCMP(zz,pz[_a])) { \
+ ptr = texture + (((t & 0x3FC00000) | s) >> 14) * 3; \
+ pp[3 * _a]= ptr[0];\
+ pp[3 * _a + 1]= ptr[1];\
+ pp[3 * _a + 2]= ptr[2];\
+ pz[_a]=zz; \
+ } \
+ z+=dzdx; \
+ s+=dsdx; \
+ t+=dtdx; \
+}
+
+#else
+
+#define PUT_PIXEL(_a) \
+{ \
+ zz=z >> ZB_POINT_Z_FRAC_BITS; \
+ if (ZCMP(zz,pz[_a])) { \
+ pp[_a]=texture[((t & 0x3FC00000) | s) >> 14]; \
+ pz[_a]=zz; \
+ } \
+ z+=dzdx; \
+ s+=dsdx; \
+ t+=dtdx; \
+}
+
+#endif
+
+#include "ztriangle.h"
+}
+
+/*
+ * Texture mapping with perspective correction.
+ * We use the gradient method to make less divisions.
+ * TODO: pipeline the division
+ */
+#if 1
+
+void ZB_fillTriangleMappingPerspective(ZBuffer *zb,
+ ZBufferPoint *p0,ZBufferPoint *p1,ZBufferPoint *p2)
+{
+ PIXEL *texture;
+ float fdzdx,fndzdx,ndszdx,ndtzdx;
+
+#define INTERP_Z
+#define INTERP_STZ
+
+#define NB_INTERP 8
+
+#define DRAW_INIT() \
+{ \
+ texture=zb->current_texture;\
+ fdzdx=(float)dzdx;\
+ fndzdx=NB_INTERP * fdzdx;\
+ ndszdx=NB_INTERP * dszdx;\
+ ndtzdx=NB_INTERP * dtzdx;\
+}
+
+
+#if TGL_FEATURE_RENDER_BITS == 24
+
+#define PUT_PIXEL(_a) \
+{ \
+ unsigned char *ptr;\
+ zz=z >> ZB_POINT_Z_FRAC_BITS; \
+ if (ZCMP(zz,pz[_a])) { \
+ ptr = texture + (((t & 0x3FC00000) | (s & 0x003FC000)) >> 14) * 3;\
+ pp[3 * _a]= ptr[0];\
+ pp[3 * _a + 1]= ptr[1];\
+ pp[3 * _a + 2]= ptr[2];\
+ pz[_a]=zz; \
+ } \
+ z+=dzdx; \
+ s+=dsdx; \
+ t+=dtdx; \
+}
+
+#else
+
+#define PUT_PIXEL(_a) \
+{ \
+ zz=z >> ZB_POINT_Z_FRAC_BITS; \
+ if (ZCMP(zz,pz[_a])) { \
+ pp[_a]=*(PIXEL *)((char *)texture+ \
+ (((t & 0x3FC00000) | (s & 0x003FC000)) >> (17 - PSZSH)));\
+ pz[_a]=zz; \
+ } \
+ z+=dzdx; \
+ s+=dsdx; \
+ t+=dtdx; \
+}
+
+#endif
+
+#define DRAW_LINE() \
+{ \
+ register unsigned short *pz; \
+ register PIXEL *pp; \
+ register unsigned int s,t,z,zz; \
+ register int n,dsdx,dtdx; \
+ float sz,tz,fz,zinv; \
+ n=(x2>>16)-x1; \
+ fz=(float)z1;\
+ zinv=1.0 / fz;\
+ pp=(PIXEL *)((char *)pp1 + x1 * PSZB); \
+ pz=pz1+x1; \
+ z=z1; \
+ sz=sz1;\
+ tz=tz1;\
+ while (n>=(NB_INTERP-1)) { \
+ {\
+ float ss,tt;\
+ ss=(sz * zinv);\
+ tt=(tz * zinv);\
+ s=(int) ss;\
+ t=(int) tt;\
+ dsdx= (int)( (dszdx - ss*fdzdx)*zinv );\
+ dtdx= (int)( (dtzdx - tt*fdzdx)*zinv );\
+ fz+=fndzdx;\
+ zinv=1.0 / fz;\
+ }\
+ PUT_PIXEL(0); \
+ PUT_PIXEL(1); \
+ PUT_PIXEL(2); \
+ PUT_PIXEL(3); \
+ PUT_PIXEL(4); \
+ PUT_PIXEL(5); \
+ PUT_PIXEL(6); \
+ PUT_PIXEL(7); \
+ pz+=NB_INTERP; \
+ pp=(PIXEL *)((char *)pp + NB_INTERP * PSZB);\
+ n-=NB_INTERP; \
+ sz+=ndszdx;\
+ tz+=ndtzdx;\
+ } \
+ {\
+ float ss,tt;\
+ ss=(sz * zinv);\
+ tt=(tz * zinv);\
+ s=(int) ss;\
+ t=(int) tt;\
+ dsdx= (int)( (dszdx - ss*fdzdx)*zinv );\
+ dtdx= (int)( (dtzdx - tt*fdzdx)*zinv );\
+ }\
+ while (n>=0) { \
+ PUT_PIXEL(0); \
+ pz+=1; \
+ pp=(PIXEL *)((char *)pp + PSZB);\
+ n-=1; \
+ } \
+}
+
+#include "ztriangle.h"
+}
+
+#endif
+
+#if 0
+
+/* slow but exact version (only there for reference, incorrect for 24
+ bits) */
+
+void ZB_fillTriangleMappingPerspective(ZBuffer *zb,
+ ZBufferPoint *p0,ZBufferPoint *p1,ZBufferPoint *p2)
+{
+ PIXEL *texture;
+
+#define INTERP_Z
+#define INTERP_STZ
+
+#define DRAW_INIT() \
+{ \
+ texture=zb->current_texture; \
+}
+
+#define PUT_PIXEL(_a) \
+{ \
+ float zinv; \
+ int s,t; \
+ zz=z >> ZB_POINT_Z_FRAC_BITS; \
+ if (ZCMP(zz,pz[_a])) { \
+ zinv= 1.0 / (float) z; \
+ s= (int) (sz * zinv); \
+ t= (int) (tz * zinv); \
+ pp[_a]=texture[((t & 0x3FC00000) | s) >> 14]; \
+ pz[_a]=zz; \
+ } \
+ z+=dzdx; \
+ sz+=dszdx; \
+ tz+=dtzdx; \
+}
+
+#include "ztriangle.h"
+}
+
+
+#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-02 08:53:09 +0000