BitHeaven
/
picom
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Make the shadow actually gaussian 

The old shadow kernel formula is not "wrong" per se, as the only judge
is if it looks good. However, the formula used is not really gaussian.
Also, the kernel size calculation doesn't really make sense to me.

This commit change the kernel formula to actually use a gaussian
distribution. As far as I can tell, there is no perceivable difference.
Except now the effective shadow radius is smaller for the same config.

Also, made that part of code a bit more mordern.

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
This commit is contained in:
Yuxuan Shui 2018-12-09 02:04:00 +00:00
parent da3df75a8c
commit dffde065b1
No known key found for this signature in database
GPG Key ID: 37C999F617EA1A47
2 changed files with 23 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/common.h
View File

@ -426,7 +426,7 @@ typedef uint32_t glx_prog_main_t;
typedef struct conv { typedef struct conv {
int size; int size;
double *data; double data[];
} conv; } conv;
/// Linked list type of atoms. /// Linked list type of atoms.

38
src/compton.c
View File

@ -569,36 +569,42 @@ check_fade_fin(session_t *ps, win **_w) {
static double __attribute__((const)) static double __attribute__((const))
gaussian(double r, double x, double y) { gaussian(double r, double x, double y) {
return ((1 / (sqrt(2 * M_PI * r))) * // Formula can be found here:
exp((- (x * x + y * y)) / (2 * r * r))); // https://en.wikipedia.org/wiki/Gaussian_blur#Mathematics
// Except a special case for r == 0 to produce sharp shadows
if (r == 0)
return 1;
return exp(-0.5*(x*x+y*y)/(r*r))/(2*M_PI*r*r);
} }
static conv * static conv *
make_gaussian_map(double r) { make_gaussian_map(double r) {
conv *c; conv *c;
int size = ((int) ceil((r * 3)) + 1) & ~1; int size = r*2+1;
int center = size / 2; int center = size/2;
int x, y;
double t; double t;
double g;
c = malloc(sizeof(conv) + size * size * sizeof(double)); c = malloc(sizeof(conv)+size*size*sizeof(double));
c->size = size; c->size = size;
c->data = (double *) (c + 1);
t = 0.0; t = 0.0;
for (y = 0; y < size; y++) { /*printf_errf("(): %f", r);*/
for (x = 0; x < size; x++) { for (int y = 0; y < size; y++) {
g = gaussian(r, x - center, y - center); for (int x = 0; x < size; x++) {
double g = gaussian(r, x-center, y-center);
t += g; t += g;
c->data[y * size + x] = g; c->data[y*size+x] = g;
/*printf("%f ", c->data[y*size+x]);*/
} }
/*printf("\n");*/
} }
for (y = 0; y < size; y++) { for (int y = 0; y < size; y++) {
for (x = 0; x < size; x++) { for (int x = 0; x < size; x++) {
c->data[y * size + x] /= t; c->data[y*size+x] /= t;
/*printf("%f ", c->data[y*size+x]);*/
} }
/*printf("\n");*/
} }
return c; return c;
@ -4227,7 +4233,7 @@ get_cfg(session_t *ps, int argc, char *const *argv, bool first_pass) {
// Range checking and option assignments // Range checking and option assignments
ps->o.fade_delta = max_i(ps->o.fade_delta, 1); ps->o.fade_delta = max_i(ps->o.fade_delta, 1);
ps->o.shadow_radius = max_i(ps->o.shadow_radius, 1); ps->o.shadow_radius = max_i(ps->o.shadow_radius, 0);
ps->o.shadow_red = normalize_d(ps->o.shadow_red); ps->o.shadow_red = normalize_d(ps->o.shadow_red);
ps->o.shadow_green = normalize_d(ps->o.shadow_green); ps->o.shadow_green = normalize_d(ps->o.shadow_green);
ps->o.shadow_blue = normalize_d(ps->o.shadow_blue); ps->o.shadow_blue = normalize_d(ps->o.shadow_blue);