Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

444 lines (370 sloc) 9.035 kb
#include "regmach.h"
#include <float.h>
#include "imageri.h"
/*#define DEBUG*/
#ifdef DEBUG
#define DBG(x) printf x
#else
#define DBG(x)
#endif
static float MAX_EXP_ARG; /* = log(DBL_MAX); */
/* these functions currently assume RGB images - there seems to be some
support for other color spaces, but I can't tell how you find what
space an image is using.
HSV conversions from pages 401-403 "Procedural Elements for Computer
Graphics", 1985, ISBN 0-07-053534-5. The algorithm presents to produce
an HSV color calculates all components at once - I don't, so I've
simiplified the algorithm to avoid unnecessary calculation (any errors
(of which I had a few ;) are mine).
*/
/* returns the value (brightness) of color from 0 to 1 */
static double hsv_value(i_color color) {
return i_max(i_max(color.rgb.r, color.rgb.g), color.rgb.b) / 255.0;
}
/* returns the hue (color) of color from 0 to 360 */
static double hsv_hue(i_color color) {
int val;
int temp;
temp = i_min(i_min(color.rgb.r, color.rgb.g), color.rgb.b);
val = i_max(color.rgb.r, i_max(color.rgb.g, color.rgb.b));
if (val == 0 || val==temp) {
return 0;
}
else {
double cr = (val - color.rgb.r) / (double)(val - temp);
double cg = (val - color.rgb.g) / (double)(val - temp);
double cb = (val - color.rgb.b) / (double)(val - temp);
double hue;
if (color.rgb.r == val) {
hue = cb-cg;
}
else if (color.rgb.g == val) {
hue = 2.0 + cr-cb;
}
else { /* if (blue == val) */
hue = 4.0 + cg - cr;
}
hue *= 60.0; /* to degrees */
if (hue < 0)
hue += 360;
return hue;
}
}
/* return the saturation of color from 0 to 1 */
static double hsv_sat(i_color color) {
int value = i_max(i_max(color.rgb.r, color.rgb.g), color.rgb.b);
if (value == 0) {
return 0;
}
else {
int temp = i_min(i_min(color.rgb.r, color.rgb.g), color.rgb.b);
return (value - temp) / (double)value;
}
}
static i_color make_hsv(double hue, double sat, double val, int alpha) {
int i;
i_color c;
for( i=0; i< MAXCHANNELS; i++) c.channel[i]=0;
DBG(("hsv=%f %f %f\n", hue, sat, val));
if (sat <= 0) { /* handle -ve in case someone supplies a bad value */
/* should this be * 256? */
c.rgb.r = c.rgb.g = c.rgb.b = 255 * val;
}
else {
int i, m, n, k, v;
double f;
if (val < 0) val = 0;
if (val > 1) val = 1;
if (sat > 1) sat = 1;
/* I want to handle -360 <= hue < 720 so that the caller can
fiddle with colour
*/
if (hue >= 360)
hue -= 360;
else if (hue < 0)
hue += 360;
hue /= 60;
i = hue; /* floor */
f = hue - i;
val *= 255;
m = val * (1.0 - sat);
n = val * (1.0 - sat * f);
k = val * (1.0 - sat * (1 - f));
v = val;
switch (i) {
case 0:
c.rgb.r = v; c.rgb.g = k; c.rgb.b = m;
break;
case 1:
c.rgb.r = n; c.rgb.g = v; c.rgb.b = m;
break;
case 2:
c.rgb.r = m; c.rgb.g = v; c.rgb.b = k;
break;
case 3:
c.rgb.r = m; c.rgb.g = n; c.rgb.b = v;
break;
case 4:
c.rgb.r = k; c.rgb.g = m; c.rgb.b = v;
break;
case 5:
c.rgb.r = v; c.rgb.g = m; c.rgb.b = n;
break;
}
}
c.rgba.a = alpha;
return c;
}
static i_color make_rgb(int r, int g, int b, int a) {
i_color c;
if (r < 0)
r = 0;
if (r > 255)
r = 255;
c.rgb.r = r;
if (g < 0)
g = 0;
if (g > 255)
g = 255;
c.rgb.g = g;
if (b < 0)
b = 0;
if (b > 255)
b = 255;
c.rgb.b = b;
c.rgba.a = a;
return c;
}
/* greatly simplifies the code */
#define nout n_regs[codes->rout]
#define na n_regs[codes->ra]
#define nb n_regs[codes->rb]
#define nc n_regs[codes->rc]
#define nd n_regs[codes->rd]
#define cout c_regs[codes->rout]
#define ca c_regs[codes->ra]
#define cb c_regs[codes->rb]
#define cc c_regs[codes->rc]
#define cd c_regs[codes->rd]
/* this is a pretty poor epsilon used for loosening up equality comparisons
It isn't currently used for inequalities
*/
#define n_epsilon(x, y) (fabs(x)+fabs(y))*0.001
static i_color bcol = {{ 0 }};
i_color i_rm_run(struct rm_op codes[], size_t code_count,
double n_regs[], size_t n_regs_count,
i_color c_regs[], size_t c_regs_count,
i_img *images[], size_t image_count) {
double dx, dy;
struct rm_op *codes_base = codes;
size_t count_base = code_count;
DBG(("rm_run(%p, %d)\n", codes, code_count));
while (code_count) {
DBG((" rm_code %d\n", codes->code));
switch (codes->code) {
case rbc_add:
nout = na + nb;
break;
case rbc_subtract:
nout = na - nb;
break;
case rbc_mult:
nout = na * nb;
break;
case rbc_div:
if (fabs(nb) < 1e-10)
nout = 1e10;
else
nout = na / nb;
break;
case rbc_mod:
if (fabs(nb) > 1e-10) {
nout = fmod(na, nb);
}
else {
nout = 0; /* close enough ;) */
}
break;
case rbc_pow:
nout = pow(na, nb);
break;
case rbc_uminus:
nout = -na;
break;
case rbc_multp:
cout = make_rgb(ca.rgb.r * nb, ca.rgb.g * nb, ca.rgb.b * nb, 255);
break;
case rbc_addp:
cout = make_rgb(ca.rgb.r + cb.rgb.r, ca.rgb.g + cb.rgb.g,
ca.rgb.b + cb.rgb.b, 255);
break;
case rbc_subtractp:
cout = make_rgb(ca.rgb.r - cb.rgb.r, ca.rgb.g - cb.rgb.g,
ca.rgb.b - cb.rgb.b, 255);
break;
case rbc_sin:
nout = sin(na);
break;
case rbc_cos:
nout = cos(na);
break;
case rbc_atan2:
nout = atan2(na, nb);
break;
case rbc_sqrt:
nout = sqrt(na);
break;
case rbc_distance:
dx = na-nc;
dy = nb-nd;
nout = sqrt(dx*dx+dy*dy);
break;
case rbc_getp1:
i_gpix(images[0], na, nb, c_regs+codes->rout);
if (images[0]->channels < 4) cout.rgba.a = 255;
break;
case rbc_getp2:
i_gpix(images[1], na, nb, c_regs+codes->rout);
if (images[1]->channels < 4) cout.rgba.a = 255;
break;
case rbc_getp3:
i_gpix(images[2], na, nb, c_regs+codes->rout);
if (images[2]->channels < 4) cout.rgba.a = 255;
break;
case rbc_value:
nout = hsv_value(ca);
break;
case rbc_hue:
nout = hsv_hue(ca);
break;
case rbc_sat:
nout = hsv_sat(ca);
break;
case rbc_hsv:
cout = make_hsv(na, nb, nc, 255);
break;
case rbc_hsva:
cout = make_hsv(na, nb, nc, nd);
break;
case rbc_red:
nout = ca.rgb.r;
break;
case rbc_green:
nout = ca.rgb.g;
break;
case rbc_blue:
nout = ca.rgb.b;
break;
case rbc_alpha:
nout = ca.rgba.a;
break;
case rbc_rgb:
cout = make_rgb(na, nb, nc, 255);
break;
case rbc_rgba:
cout = make_rgb(na, nb, nc, nd);
break;
case rbc_int:
nout = (int)(na);
break;
case rbc_if:
nout = na ? nb : nc;
break;
case rbc_ifp:
cout = na ? cb : cc;
break;
case rbc_le:
nout = na <= nb + n_epsilon(na,nb);
break;
case rbc_lt:
nout = na < nb;
break;
case rbc_ge:
nout = na >= nb - n_epsilon(na,nb);
break;
case rbc_gt:
nout = na > nb;
break;
case rbc_eq:
nout = fabs(na-nb) <= n_epsilon(na,nb);
break;
case rbc_ne:
nout = fabs(na-nb) > n_epsilon(na,nb);
break;
case rbc_and:
nout = na && nb;
break;
case rbc_or:
nout = na || nb;
break;
case rbc_not:
nout = !na;
break;
case rbc_abs:
nout = fabs(na);
break;
case rbc_ret:
return ca;
break;
case rbc_jump:
/* yes, order is important here */
code_count = count_base - codes->ra;
codes = codes_base + codes->ra;
continue;
case rbc_jumpz:
if (!na) {
/* yes, order is important here */
code_count = count_base - codes->rb;
codes = codes_base + codes->rb;
continue;
}
break;
case rbc_jumpnz:
if (na) {
/* yes, order is important here */
code_count = count_base - codes->rb;
codes = codes_base + codes->rb;
continue;
}
break;
case rbc_set:
nout = na;
break;
case rbc_setp:
cout = ca;
break;
case rbc_log:
if (na > 0) {
nout = log(na);
}
else {
nout = DBL_MAX;
}
break;
case rbc_exp:
if (!MAX_EXP_ARG) MAX_EXP_ARG = log(DBL_MAX);
if (na <= MAX_EXP_ARG) {
nout = exp(na);
}
else {
nout = DBL_MAX;
}
break;
case rbc_print:
nout = na;
printf("r%d is %g\n", codes->ra, na);
break;
case rbc_det:
nout = na*nd-nb*nc;
break;
default:
/*croak("bad opcode"); */
printf("bad op %d\n", codes->code);
return bcol;
}
--code_count;
++codes;
}
return bcol;
/* croak("no return opcode"); */
}
Jump to Line
Something went wrong with that request. Please try again.