ref: fdae64883b3e079cbb624bb7a10d09952e191382
parent: 25a30d016d16cfed0f35bbbafe52886e96a64e1e
author: rodri <rgl@antares-labs.eu>
date: Sun Nov 12 12:25:50 EST 2023
added texture mapping.
--- a/main.c
+++ b/main.c
@@ -35,6 +35,7 @@
double *zbuf;
Memimage *red, *green, *blue;
OBJ *model;
+Memimage *modeltex;
Channel *drawc;
int nprocs;
@@ -43,6 +44,28 @@
void resized(void);
uvlong nanosec(void);
+int
+min(int a, int b)
+{
+ return a < b? a: b;
+}
+
+int
+max(int a, int b)
+{
+ return a > b? a: b;
+}
+
+void
+swap(int *a, int *b)
+{
+ int t;
+
+ t = *a;
+ *a = *b;
+ *b = t;
+}
+
void *
emalloc(ulong n)
{
@@ -96,16 +119,43 @@
return i;
}
-int
-min(int a, int b)
+static void
+decproc(void *arg)
{
- return a < b? a: b;
+ int fd, *pfd;
+
+ pfd = arg;
+ fd = pfd[2];
+
+ close(pfd[0]);
+ dup(fd, 0);
+ close(fd);
+ dup(pfd[1], 1);
+ close(pfd[1]);
+
+ execl("/bin/tga", "tga", "-9t", nil);
+ threadexitsall("execl: %r");
}
-int
-max(int a, int b)
+Memimage *
+readtga(char *path)
{
- return a > b? a: b;
+ Memimage *i;
+ int fd, pfd[3];
+
+ if(pipe(pfd) < 0)
+ sysfatal("pipe: %r");
+ fd = open(path, OREAD);
+ if(fd < 0)
+ sysfatal("open: %r");
+ pfd[2] = fd;
+ procrfork(decproc, pfd, mainstacksize, RFFDG|RFNAMEG|RFNOTEG);
+ close(pfd[1]);
+ i = readmemimage(pfd[0]);
+ close(pfd[0]);
+ close(fd);
+
+ return i;
}
Memimage *
@@ -130,16 +180,6 @@
}
void
-swap(int *a, int *b)
-{
- int t;
-
- t = *a;
- *a = *b;
- *b = t;
-}
-
-void
bresenham(Memimage *dst, Point p0, Point p1, Memimage *src)
{
int steep = 0, Δe, e, Δy;
@@ -342,19 +382,20 @@
{
OBJObject *o;
OBJElem *e;
- OBJVertex *verts;
+ OBJVertex *verts, *tverts; /* geometric and texture vertices */
OBJIndexArray *idxtab;
Triangle3 t;
- Triangle2 st;
+ Triangle2 st, tt; /* screen and texture triangles */
Rectangle bbox;
- Point3 bc;
- static Point3 light = {0,0,-1,0}; /* global light field */
- Point3 n;
+ Point3 bc, n; /* barycentric coords and surface normal */
+ static Point3 light = {0,0,-1,0}; /* global light field */
+ Point tp; /* texture point */
int i;
- uchar cbuf[4];
+ uchar cbuf[4], cbuf2[4];
double z, intensity;
verts = model->vertdata[OBJVGeometric].verts;
+ tverts = model->vertdata[OBJVTexture].verts;
for(i = 0; i < nelem(model->objtab); i++)
for(o = model->objtab[i]; o != nil; o = o->next)
@@ -398,11 +439,34 @@
if(intensity < 0)
continue;
- cbuf[0] = 0xFF;
- cbuf[1] = 0xFF*intensity;
- cbuf[2] = 0xFF*intensity;
- cbuf[3] = 0xFF*intensity;
+ idxtab = &e->indextab[OBJVTexture];
+ if(modeltex != nil && idxtab->nindex == 3){
+ tt.p0 = Pt2(tverts[idxtab->indices[0]].u, tverts[idxtab->indices[0]].v, 1);
+ tt.p1 = Pt2(tverts[idxtab->indices[1]].u, tverts[idxtab->indices[1]].v, 1);
+ tt.p2 = Pt2(tverts[idxtab->indices[2]].u, tverts[idxtab->indices[2]].v, 1);
+ tt.p0 = mulpt2(tt.p0, bc.x);
+ tt.p1 = mulpt2(tt.p1, bc.y);
+ tt.p2 = mulpt2(tt.p2, bc.z);
+
+ tp.x = (tt.p0.x + tt.p1.x + tt.p2.x)*Dx(modeltex->r);
+ tp.y = Dy(modeltex->r)-(tt.p0.y + tt.p1.y + tt.p2.y)*Dy(modeltex->r);
+
+ unloadmemimage(modeltex, rectaddpt(Rect(0,0,1,1), tp), cbuf2, sizeof cbuf2);
+ cbuf[0] = cbuf2[3];
+ cbuf[1] = cbuf2[0];
+ cbuf[2] = cbuf2[1];
+ cbuf[3] = cbuf2[2];
+ }else{
+ cbuf[0] = 0xFF;
+ cbuf[1] = 0xFF;
+ cbuf[2] = 0xFF;
+ cbuf[3] = 0xFF;
+ }
+ cbuf[1] *= intensity;
+ cbuf[2] *= intensity;
+ cbuf[3] *= intensity;
+
memfillcolor(sp->frag, *(ulong*)cbuf);
return sp->frag;
}
@@ -485,7 +549,7 @@
void
usage(void)
{
- fprint(2, "usage: %s [-n nprocs] [-m objfile]\n", argv0);
+ fprint(2, "usage: %s [-n nprocs] [-m objfile] [-t texfile]\n", argv0);
exits("usage");
}
@@ -495,10 +559,11 @@
Mousectl *mc;
Keyboardctl *kc;
Rune r;
- char *mdlpath;
+ char *mdlpath, *texpath;
GEOMfmtinstall();
mdlpath = nil;
+ texpath = nil;
ARGBEGIN{
case 'n':
nprocs = strtoul(EARGF(usage()), nil, 10);
@@ -506,6 +571,9 @@
case 'm':
mdlpath = EARGF(usage());
break;
+ case 't':
+ texpath = EARGF(usage());
+ break;
default: usage();
}ARGEND;
if(argc != 0)
@@ -535,6 +603,8 @@
if(mdlpath != nil && (model = objparse(mdlpath)) == nil)
sysfatal("objparse: %r");
+ if(texpath != nil && (modeltex = readtga(texpath)) == nil)
+ sysfatal("readtga: %r");
render();
binary files /dev/null b/tex/african_head_diffuse.tga differ