On Thu, 2004-11-25 at 14:50, Karl Ove Hufthammer wrote:
> Albert Cahalan <[EMAIL PROTECTED]> wrote in
> news:[EMAIL PROTECTED]:
>
> > On Thu, 2004-11-25 at 00:49, Albert Cahalan wrote:
> >> To show off the new tinter, the enclosed patch restores
> >> the original purple. Yellow is much, much, nicer with this
> >> new tinter.
> >
> > So... anybody try it? Any objections? Good? Bad?
>
> I got an error message while trying to apply it for tuxpaint.c.
> Could you try resending it, now as a an attachment (line-breaking
> in e-mail programs easily mangles patches) and diffed against
> latest CVS version?
Don't cut-and-paste. Save the email, then run the whole
thing through patch. If you still get an error, check to
be sure that some lame "helpful" mail gateway hasn't
decided to "prevent damage" by using printed-quotable
MIME encoding. Never use such evil mail gateways.
Remember:
cd root-of-tuxpaint-source
patch -s -E -p1 < path-to-this-email
Use the --dry-run option if you want to check first.
> But I have one comment. As far as I can see, you have completely
> removed the notintgray feature. We do really *not* want to try to
> be clever and (by default) only render parts of a stamp which has
> the same hue. This has lead to problems in the past.
>
> (But if a stamp require not tinting 'grey' parts, the 'notintgray'
> option should still be available.)
If there are problems, I'll deal with them.
I don't special-case grey. Tinting grey is a no-op.
I can change the hue, but that means nothing. Here's
what happens to it:
double u = sat * sin(mc->hue);
double v = sat * cos(mc->hue);
double L = mc->L;
As you may guess, "sat" is the saturation, which will be 0.0
for grey. So the hue doesn't matter. Both u and v become 0.0.
I'll try again with a patch in the body. This needs to work.
Attachments are hard to quote in email responses. Speaking
of which, this mailing list makes my "reply" and "group reply"
buttons to the same thing, limiting my communication choices.
---------- the patch ---------
diff -Naurd t2/src/colors.h tx/src/colors.h
--- t2/src/colors.h 2004-11-22 20:28:45.000000000 -0500
+++ tx/src/colors.h 2004-11-25 00:18:52.000000000 -0500
@@ -52,7 +52,7 @@
{ 33, 148, 33}, /* Green */
{138, 168, 205}, /* Sky blue */
{ 0, 0, 255}, /* Blue */
- { 96, 0, 128}, /* Purple */
+ {128, 0, 128}, /* Purple */
{255, 0, 255}, /* Magenta */
{128, 96, 0}, /* Brown */
{226, 189, 166}, /* Tan */
diff -Naurd t2/src/tuxpaint.c tx/src/tuxpaint.c
--- t2/src/tuxpaint.c 2004-11-24 18:35:15.000000000 -0500
+++ tx/src/tuxpaint.c 2004-11-25 00:31:35.000000000 -0500
@@ -3009,58 +3009,266 @@
}
+//////////////////////////////////////////////////////////////////////////
+// stamp tinter
+
typedef struct multichan {
double r,g,b; // linear
double L,u,v; // L,a,b would be better -- 2-way formula unknown
double hue,sat;
- unsigned char or,og,ob,oa; // old 8-bit sRGB values
- unsigned char nr,ng,nb,na; // new 8-bit sRGB values
+ unsigned char or,og,ob; // old 8-bit sRGB values
+ unsigned char nr,ng,nb; // new 8-bit sRGB values
+ unsigned char alpha; // 8-bit alpha value
} multichan;
+#define X0 ((double)0.9505)
+#define Y0 ((double)1.0000)
+#define Z0 ((double)1.0890)
+#define u0_prime ( (4.0 * X0) / (X0 + 15.0*Y0 + 3.0*Z0) )
+#define v0_prime ( (9.0 * Y0) / (X0 + 15.0*Y0 + 3.0*Z0) )
+
+static void fill_multichan(multichan *mc)
+{
+ double tmp,X,Y,Z;
+ double u_prime, v_prime; /* temp, part of official formula */
+ double Y_norm, fract; /* severely temp */
+
+ // from 8-bit sRGB to linear RGB
+ tmp = mc->or / 255.0;
+ mc->r = (tmp<=0.03928) ? tmp/12.92 : pow((tmp+0.055)/1.055,2.4);
+ tmp = mc->og / 255.0;
+ mc->g = (tmp<=0.03928) ? tmp/12.92 : pow((tmp+0.055)/1.055,2.4);
+ tmp = mc->ob / 255.0;
+ mc->b = (tmp<=0.03928) ? tmp/12.92 : pow((tmp+0.055)/1.055,2.4);
+
+ // coordinate change, RGB --> XYZ
+ X = 0.4124*mc->r + 0.3576*mc->g + 0.1805*mc->b;
+ Y = 0.2126*mc->r + 0.7152*mc->g + 0.0722*mc->b;
+ Z = 0.0193*mc->r + 0.1192*mc->g + 0.9505*mc->b;
+
+ // XYZ --> Luv
+ Y_norm = Y/Y0;
+ fract = 1.0 / (X + 15.0*Y + 3.0*Z);
+ u_prime = 4.0*X*fract;
+ v_prime = 9.0*Y*fract;
+ mc->L = (Y_norm>0.008856) ? 116.0*pow(Y_norm,1.0/3.0)-16.0 : 903.3*Y_norm;
+ mc->u = 13.0*mc->L*(u_prime - u0_prime);
+ mc->v = 13.0*mc->L*(v_prime - v0_prime);
+
+ mc->sat = sqrt(mc->u*mc->u + mc->v*mc->v);
+ mc->hue = atan2(mc->u,mc->v);
+}
+
static void tint_surface(SDL_Surface * tmp_surf, SDL_Surface * surf_ptr)
{
+ unsigned i;
+ int xx, yy;
- float col_hue, col_sat, col_val,
- stamp_hue, stamp_sat, stamp_val;
+ unsigned width = surf_ptr->w;
+ unsigned height = surf_ptr->h;
- Uint8 r, g, b, a;
- int xx, yy;
+ multichan *work = malloc(sizeof *work * width * height);
- rgbtohsv(color_hexes[cur_color][0],
- color_hexes[cur_color][1],
- color_hexes[cur_color][2],
- &col_hue, &col_sat, &col_val);
-
+ // put pixels into a more tolerable form
+ SDL_LockSurface(surf_ptr);
+ for (yy = 0; yy < surf_ptr->h; yy++)
+ {
+ for (xx = 0; xx < surf_ptr->w; xx++)
+ {
+ multichan *mc = work+yy*width+xx;
+ SDL_GetRGBA(getpixel(surf_ptr, xx, yy),
+ surf_ptr->format,
+ &mc->or, &mc->og, &mc->ob, &mc->alpha);
+ }
+ }
+ SDL_UnlockSurface(surf_ptr);
- /* Render the stamp: */
+ i = width * height;
+ while (i--)
+ {
+ multichan *mc = work+i;
+ fill_multichan(mc);
+ }
- SDL_LockSurface(surf_ptr);
- SDL_LockSurface(tmp_surf);
+ // initial hue guess
+ double alpha_total = 0;
+ double u_total = 0;
+ double v_total = 0;
+ i = width * height;
+ while (i--)
+ {
+ multichan *mc = work+i;
+ alpha_total += mc->alpha;
+ // more weight to opaque high-saturation pixels
+ u_total += mc->alpha * mc->u * mc->sat;
+ v_total += mc->alpha * mc->v * mc->sat;
+ }
+ double initial_hue = atan2(u_total,v_total);
- for (yy = 0; yy < surf_ptr->h; yy++)
- {
- for (xx = 0; xx < surf_ptr->w; xx++)
- {
- SDL_GetRGBA(getpixel(surf_ptr, xx, yy),
- surf_ptr->format,
- &r, &g, &b, &a);
-
- rgbtohsv(r, g, b, &stamp_hue, &stamp_sat, &stamp_val);
-
- if ( stamp_tintgray(cur_stamp) || stamp_sat > 0.25 )
- hsvtorgb(col_hue, col_sat, stamp_val, &r, &g, &b);
- // else
- // hsvtorgb(col_hue, col_sat, stamp_val, &r, &g, &b);
-
- putpixel(tmp_surf, xx, yy,
- SDL_MapRGBA(tmp_surf->format, r, g, b, a));
- }
+ // find the most saturated pixel near the initial hue guess
+ multichan *key_color_ptr = NULL;
+ double hue_range = 25*M_PI/180.0; // plus or minus 25 degrees (should let
stamp author decide)
+hue_range_retry:;
+ double max_sat = 0;
+ double lower_hue_1 = initial_hue - hue_range;
+ double upper_hue_1 = initial_hue + hue_range;
+ double lower_hue_2;
+ double upper_hue_2;
+ if (lower_hue_1 < -M_PI)
+ {
+ lower_hue_2 = lower_hue_1 + 2 * M_PI;
+ upper_hue_2 = upper_hue_1 + 2 * M_PI;
+ }
+ else
+ {
+ lower_hue_2 = lower_hue_1 - 2 * M_PI;
+ upper_hue_2 = upper_hue_1 - 2 * M_PI;
+ }
+ i = width * height;
+ while (i--)
+ {
+ multichan *mc = work+i;
+ // if not in the first range, and not in the second range, skip this one
+ if( (mc->hue<lower_hue_1 || mc->hue>upper_hue_1) && (mc->hue<lower_hue_2
|| mc->hue>upper_hue_2) )
+ continue;
+ if(mc->sat > max_sat) {
+ max_sat = mc->sat;
+ key_color_ptr = mc;
+ }
+ }
+ if (!key_color_ptr)
+ {
+ hue_range *= 1.5;
+ if (hue_range < M_PI)
+ goto hue_range_retry;
+ goto give_up;
+ }
+
+
+ // prepare source and destination color info
+ // should reset hue_range or not? won't bother for now
+ multichan key_color = *key_color_ptr; // want to work from a copy, for safety
+ lower_hue_1 = key_color.hue - hue_range;
+ upper_hue_1 = key_color.hue + hue_range;
+ if (lower_hue_1 < -M_PI)
+ {
+ lower_hue_2 = lower_hue_1 + 2 * M_PI;
+ upper_hue_2 = upper_hue_1 + 2 * M_PI;
+ }
+ else
+ {
+ lower_hue_2 = lower_hue_1 - 2 * M_PI;
+ upper_hue_2 = upper_hue_1 - 2 * M_PI;
+ }
+
+ // get the destination color set up
+ multichan dst;
+ dst.or = color_hexes[cur_color][0];
+ dst.og = color_hexes[cur_color][1];
+ dst.ob = color_hexes[cur_color][2];
+ fill_multichan(&dst);
+ double satratio = dst.sat / key_color.sat;
+ double slope = (dst.L-key_color.L)/dst.sat;
+
+ // change the colors!
+ i = width * height;
+ while (i--)
+ {
+ multichan *mc = work+i;
+ // if not in the first range, and not in the second range, skip this one
+ // (really should alpha-blend as a function of hue angle difference)
+ if( (mc->hue<lower_hue_1 || mc->hue>upper_hue_1) && (mc->hue<lower_hue_2
|| mc->hue>upper_hue_2) )
+ continue;
+ // this one will now be modified
+ double old_sat = mc->sat;
+ mc->hue = dst.hue;
+ mc->sat = mc->sat * satratio;
+ if(dst.sat>0)
+ mc->L += mc->sat * slope; // not greyscale destination
+ else
+ mc->L += old_sat*(dst.L-key_color.L)/key_color.sat;
+ }
+
+give_up:
+
+ i = width * height;
+ while (i--)
+ {
+ multichan *mc = work+i;
+ double X,Y,Z;
+ double u_prime, v_prime; /* temp, part of official formula */
+ int r,g,b;
+ unsigned tries = 3;
+ double sat = mc->sat;
+trysat:;
+ double u = sat * sin(mc->hue);
+ double v = sat * cos(mc->hue);
+ double L = mc->L;
+
+ // Luv to XYZ
+ u_prime = u/(13.0*L)+u0_prime;
+ v_prime = v/(13.0*L)+v0_prime;
+ Y = (L>7.99959199307) ? Y0*pow((L+16.0)/116.0,3.0) : Y0*L/903.3;
+ X = 2.25*Y*u_prime/v_prime;
+ Z = (3.0*Y - 0.75*Y*u_prime)/v_prime - 5.0*Y;
+
+ // coordinate change: XYZ to RGB
+ mc->r = 3.2410*X + -1.5374*Y + -0.4986*Z;
+ mc->g = -0.9692*X + 1.8760*Y + 0.0416*Z;
+ mc->b = 0.0556*X + -0.2040*Y + 1.0570*Z;
+
+ // gamma: linear to sRGB
+ r = ( (mc->r<=0.00304) ? 12.92*mc->r : 1.055*pow(mc->r,1.0/2.4)-0.055 )
* 255.9999;
+ g = ( (mc->g<=0.00304) ? 12.92*mc->g : 1.055*pow(mc->g,1.0/2.4)-0.055 )
* 255.9999;
+ b = ( (mc->b<=0.00304) ? 12.92*mc->b : 1.055*pow(mc->b,1.0/2.4)-0.055 )
* 255.9999;
+
+ if((r|g|b)>>8){
+ static int cnt = 42;
+ if(cnt){
+ cnt--;
+// printf("%d %d %d\n",r,g,b);
}
+ sat *= 0.8;
+ if(tries--)
+ goto trysat; // maybe it'll work if we de-saturate a bit
+ else
+ { // bummer, this is out of gamut and fighting
+ if (r>255)
+ r = 255;
+ if (g>255)
+ g = 255;
+ if (b>255)
+ b = 255;
+ if (r<0)
+ r = 0;
+ if (g<0)
+ g = 0;
+ if (b<0)
+ b = 0;
+ }
+ }
+
+ mc->nr = r;
+ mc->ng = g;
+ mc->nb = b;
+ }
- SDL_UnlockSurface(tmp_surf);
- SDL_UnlockSurface(surf_ptr);
+ // put data back into SDL form
+ SDL_LockSurface(tmp_surf);
+ for (yy = 0; yy < tmp_surf->h; yy++)
+ {
+ for (xx = 0; xx < tmp_surf->w; xx++)
+ {
+ multichan *mc = work+yy*width+xx;
+ putpixel(tmp_surf, xx, yy,
+ SDL_MapRGBA(tmp_surf->format, mc->nr, mc->ng, mc->nb,
mc->alpha));
+ }
+ }
+ SDL_UnlockSurface(tmp_surf);
}
+//////////////////////////////////////////////////////////////////////
+
/* Draw using the current stamp: */
static void stamp_draw(int x, int y)
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