HIDDEN int
fr_miss(struct application *ap)
{
RT_CK_AP(ap);
fr_global_head.pt_forw = fr_global_head.pt_back = &fr_global_head;
return 0;
}
HIDDEN int
fr_hit(struct application *ap, struct partition *headp, struct seg *segp)
{
RT_CK_AP(ap);
RT_CK_PT_HD(headp);
if (segp) RT_CK_SEG(segp);
if (headp->pt_forw == headp) return 0;
/* Steal the linked list, hang it off a global header */
fr_global_head.pt_forw = headp->pt_forw;
fr_global_head.pt_back = headp->pt_back;
fr_global_head.pt_back->pt_forw = &fr_global_head;
fr_global_head.pt_forw->pt_back = &fr_global_head;
headp->pt_forw = headp->pt_back = headp;
return 1;
}
/*
* Given a u, v coordinate within the texture (0 <= u, v <= 1.0),
* return a pointer to the relevant pixel.
*
* Note that .pix files are stored left-to-right, bottom-to-top,
* which works out very naturally for the indexing scheme.
*/
HIDDEN int
txt_render(struct application *ap, const struct partition *pp, struct shadework *swp, void *dp)
{
register struct txt_specific *tp =
(struct txt_specific *)dp;
fastf_t xmin, xmax, ymin, ymax;
int dx, dy;
register fastf_t r, g, b;
struct uvcoord uvc;
long tmp;
RT_CK_AP(ap);
RT_CHECK_PT(pp);
uvc = swp->sw_uv;
if (rdebug & RDEBUG_SHADE)
bu_log("in txt_render(): du=%g, dv=%g\n",
uvc.uv_du, uvc.uv_dv);
/* take care of scaling U, V coordinates to get the desired amount
* of replication of the texture
*/
uvc.uv_u *= tp->tx_scale[X];
tmp = uvc.uv_u;
uvc.uv_u -= tmp;
if (tp->tx_mirror && (tmp & 1))
uvc.uv_u = 1.0 - uvc.uv_u;
uvc.uv_v *= tp->tx_scale[Y];
tmp = uvc.uv_v;
uvc.uv_v -= tmp;
if (tp->tx_mirror && (tmp & 1))
uvc.uv_v = 1.0 - uvc.uv_v;
uvc.uv_du /= tp->tx_scale[X];
uvc.uv_dv /= tp->tx_scale[Y];
/*
* If no texture file present, or if
* texture isn't and can't be read, give debug colors
*/
if ((bu_vls_strlen(&tp->tx_name) <= 0) || (!tp->tx_mp && !tp->tx_binunifp)) {
bu_log("WARNING: texture [%s] could not be read\n", bu_vls_addr(&tp->tx_name));
VSET(swp->sw_color, uvc.uv_u, 0, uvc.uv_v);
if (swp->sw_reflect > 0 || swp->sw_transmit > 0)
(void)rr_render(ap, pp, swp);
return 1;
}
/* u is left->right index, v is line number bottom->top */
/* Don't filter more than 1/8 of the texture for 1 pixel! */
if (uvc.uv_du > 0.125) uvc.uv_du = 0.125;
if (uvc.uv_dv > 0.125) uvc.uv_dv = 0.125;
if (uvc.uv_du < 0 || uvc.uv_dv < 0) {
bu_log("txt_render uv=%g, %g, du dv=%g %g seg=%s\n",
uvc.uv_u, uvc.uv_v, uvc.uv_du, uvc.uv_dv,
pp->pt_inseg->seg_stp->st_name);
uvc.uv_du = uvc.uv_dv = 0;
}
xmin = uvc.uv_u - uvc.uv_du;
xmax = uvc.uv_u + uvc.uv_du;
ymin = uvc.uv_v - uvc.uv_dv;
ymax = uvc.uv_v + uvc.uv_dv;
if (xmin < 0) xmin = 0;
if (ymin < 0) ymin = 0;
if (xmax > 1) xmax = 1;
if (ymax > 1) ymax = 1;
if (rdebug & RDEBUG_SHADE)
bu_log("footprint in texture space is (%g %g) <-> (%g %g)\n",
xmin * (tp->tx_w-1), ymin * (tp->tx_n-1),
xmax * (tp->tx_w-1), ymax * (tp->tx_n-1));
dx = (int)(xmax * (tp->tx_w-1)) - (int)(xmin * (tp->tx_w-1));
dy = (int)(ymax * (tp->tx_n-1)) - (int)(ymin * (tp->tx_n-1));
if (rdebug & RDEBUG_SHADE)
bu_log("\tdx = %d, dy = %d\n", dx, dy);
if (dx == 0 && dy == 0) {
/* No averaging necessary */
register unsigned char *cp=NULL;
if (tp->tx_mp) {
cp = ((unsigned char *)(tp->tx_mp->buf)) +
(int)(ymin * (tp->tx_n-1)) * tp->tx_w * 3 +
(int)(xmin * (tp->tx_w-1)) * 3;
} else if (tp->tx_binunifp) {
cp = ((unsigned char *)(tp->tx_binunifp->u.uint8)) +
(int)(ymin * (tp->tx_n-1)) * tp->tx_w * 3 +
(int)(xmin * (tp->tx_w-1)) * 3;
} else {
bu_bomb("sh_text.c -- No texture data found\n");
}
r = *cp++;
g = *cp++;
b = *cp;
} else {
/* Calculate weighted average of cells in footprint */
fastf_t tot_area = 0.0;
fastf_t cell_area;
int start_line, stop_line, line;
int start_col, stop_col, col;
fastf_t xstart, xstop, ystart, ystop;
xstart = xmin * (tp->tx_w-1);
xstop = xmax * (tp->tx_w-1);
ystart = ymin * (tp->tx_n-1);
ystop = ymax * (tp->tx_n-1);
start_line = ystart;
stop_line = ystop;
start_col = xstart;
stop_col = xstop;
r = g = b = 0.0;
if (rdebug & RDEBUG_SHADE) {
bu_log("\thit in texture space = (%g %g)\n", uvc.uv_u * (tp->tx_w-1), uvc.uv_v * (tp->tx_n-1));
bu_log("\t averaging from (%g %g) to (%g %g)\n", xstart, ystart, xstop, ystop);
bu_log("\tcontributions to average:\n");
}
for (line = start_line; line <= stop_line; line++) {
register unsigned char *cp=NULL;
fastf_t line_factor;
fastf_t line_upper, line_lower;
line_upper = line + 1.0;
if (line_upper > ystop)
line_upper = ystop;
line_lower = line;
if (line_lower < ystart)
line_lower = ystart;
line_factor = line_upper - line_lower;
if (tp->tx_mp) {
cp = ((unsigned char *)(tp->tx_mp->buf)) +
line * tp->tx_w * 3 + (int)(xstart) * 3;
} else if (tp->tx_binunifp) {
cp = ((unsigned char *)(tp->tx_binunifp->u.uint8)) +
line * tp->tx_w * 3 + (int)(xstart) * 3;
} else {
/* not reachable */
bu_bomb("sh_text.c -- Unable to read datasource\n");
}
for (col = start_col; col <= stop_col; col++) {
fastf_t col_upper, col_lower;
col_upper = col + 1.0;
if (col_upper > xstop) col_upper = xstop;
col_lower = col;
if (col_lower < xstart) col_lower = xstart;
cell_area = line_factor * (col_upper - col_lower);
tot_area += cell_area;
if (rdebug & RDEBUG_SHADE)
bu_log("\t %d %d %d weight=%g (from col=%d line=%d)\n", *cp, *(cp+1), *(cp+2), cell_area, col, line);
r += (*cp++) * cell_area;
g += (*cp++) * cell_area;
b += (*cp++) * cell_area;
}
}
r /= tot_area;
g /= tot_area;
b /= tot_area;
}
if (rdebug & RDEBUG_SHADE)
bu_log(" average: %g %g %g\n", r, g, b);
if (!tp->tx_trans_valid) {
opaque:
VSET(swp->sw_color,
r / 255.0,
g / 255.0,
b / 255.0);
if (swp->sw_reflect > 0 || swp->sw_transmit > 0)
(void)rr_render(ap, pp, swp);
return 1;
}
/* This circumlocution needed to keep expression simple for Cray,
* and others
*/
if (!EQUAL(r, ((long)tp->tx_transp[0]))) goto opaque;
if (!EQUAL(g, ((long)tp->tx_transp[1]))) goto opaque;
if (!EQUAL(b, ((long)tp->tx_transp[2]))) goto opaque;
/*
* Transparency mapping is enabled, and we hit a transparent spot.
* Let higher level handle it in reflect/refract code.
*/
swp->sw_transmit = 1.0;
swp->sw_reflect = 0.0;
bu_log("leaving txt_render()\n");
if (swp->sw_reflect > 0 || swp->sw_transmit > 0)
(void)rr_render(ap, pp, swp);
return 1;
}
