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Major Fold magic tool improvements by Pere.

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This commit is contained in:
William Kendrick 2009-03-01 22:50:32 +00:00
parent d44d50822f
commit 8f7477d4b6
3 changed files with 351 additions and 135 deletions
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6
docs/AUTHORS.txt
View file

@ -7,7 +7,7 @@ bill@newbreedsoftware.com
http://www.tuxpaint.org/
June 17, 2002 - January 30, 2009
June 17, 2002 - March 1, 2009
$Id$
@ -57,11 +57,11 @@ $Id$
by Andrew 'akanewbie' Corcoran <akanewbie@gmail.com>
Contributed as part of Google Summer of Code, 2008.
Confetti, Fold, Fisheye, TV, Rosette, Picasso and Wavelets Magic Tools.
Confetti, Fisheye, TV, Rosette, Picasso and Wavelets Magic Tools.
by Adam 'foo-script' Rakowski <foo-script@o2.pl>
Contributed as part of Google Summer of Code, 2008.
Rails Magic Tool
Rails and Fold Magic Tools
by Adam 'foo-script' Rakowski <foo-script@o2.pl> (part of GSOC 2008)
with modifications by Bill Kendrick
and Pere Pujal i Carabantes <pere@fornol.no-ip.org>

6
docs/CHANGES.txt
View file

@ -8,7 +8,7 @@ http://www.tuxpaint.org/
$Id$
2009.February.22 (0.9.21)
2009.March.1 (0.9.21)
* New Starters:
-------------
* Silver Frame
@ -35,7 +35,6 @@ $Id$
(Part of Tux4Kids' participation in Google Summer of Code 2008)
* + Confetti - Paints random confetti bits on the canvas.
+ Fold - Folds the corners of the image up, like a piece of paper.
+ Fisheye - Warps part of the picture, as though seen through a fisheye.
+ TV - Adds television (CRT) interlacing lines over the image.
+ Rosette - Paints at 3 points on the screen, in a rosette shape.
@ -44,7 +43,8 @@ $Id$
By Adam 'foo-script' Rakowski <foo-script@o2.pl>
(Part of Tux4Kids' participation in Google Summer of Code 2008)
* Rails - Draws train tracks / rails over the image.
* + Rails - Draws train tracks / rails over the image.
+ Fold - Folds the corners of the image up, like a piece of paper.
By Adam 'foo-script' Rakowski <foo-script@o2.pl> (GSOC 2008),
with modifications by Bill Kendrick
and Pere Pujal i Carabantes <pere@fornol.no-ip.org>

474
magic/src/fold.c
View file

@ -8,11 +8,33 @@
#define FOLD_LEN 80
int right_arm_x, right_arm_y, left_arm_x, left_arm_y;
int fold_ox, fold_oy;
int fold_x, fold_y;
Uint8 fold_shadow_value;
Uint8 corner;
Mix_Chunk * fold_snd;
Uint8 fold_r, fold_g, fold_b;
Uint32 fold_color;
SDL_Surface * fold_surface_src, * fold_surface_dst;
void fold_draw(magic_api * api, int which,
SDL_Surface * canvas, SDL_Surface * snapshot,
int x, int y, SDL_Rect * update_rect);
static void fold_erase(void * ptr, int which, SDL_Surface * canvas, SDL_Surface * last,
int x, int y);
void translate_coords(SDL_Surface * canvas,int angle);
SDL_Surface * rotate(magic_api * api, SDL_Surface * canvas, int angle);
void fold_draw(magic_api * api, int which,
SDL_Surface * canvas, SDL_Surface * snapshot,
int x, int y, SDL_Rect * update_rect);
static void fold_print_line(void * ptr, int which, SDL_Surface * canvas, SDL_Surface * last,
int x, int y);
static void fold_print_dark_line(void * ptr, int which, SDL_Surface * canvas, SDL_Surface * last,
int x, int y);
void translate_xy(SDL_Surface * canvas, int x, int y, int * a, int * b, int rotation);
// Housekeeping functions
void fold_drag(magic_api * api, int which, SDL_Surface * canvas,
@ -63,11 +85,246 @@ char * fold_get_description(magic_api * api, int which, int mode) { return strdu
int fold_requires_colors(magic_api * api, int which) { return 1; } //selected color will be a "backpage" color
static void fold_shadow(void * ptr, int which, SDL_Surface * canvas, SDL_Surface * temp,
int x, int y)
{
magic_api * api = (magic_api *) ptr;
Uint8 r,g,b,a;
SDL_GetRGBA(api->getpixel(temp, x, y),
temp->format, &r, &g, &b, &a);
api->putpixel(canvas, x, y, SDL_MapRGBA(canvas->format,
max(r-160+fold_shadow_value*4,0), max(g-160+fold_shadow_value*4,0), max(b-160+fold_shadow_value*4,0), a));
}
void fold_draw(magic_api * api, int which,
SDL_Surface * canvas, SDL_Surface * snapshot,
int x, int y, SDL_Rect * update_rect)
{
float right_step_x, right_step_y, left_step_x, left_step_y;
float dist_x, dist_y;
int left_y, right_x;
float w, h;
SDL_Surface * temp;
temp=SDL_CreateRGBSurface(SDL_ANYFORMAT, canvas->w, canvas->h, canvas->format->BitsPerPixel,
canvas->format->Rmask, canvas->format->Gmask, canvas->format->Bmask, canvas->format->Amask);
SDL_BlitSurface(canvas,0,temp,0);
right_step_x=(float)(x-left_arm_x)/(float)(left_arm_x-fold_ox);
right_step_y=(float)(y-left_arm_y)/(float)(left_arm_x-fold_ox);
left_step_x=(float)(x-right_arm_x)/(float)(right_arm_y-fold_oy);
left_step_y=(float)(y-right_arm_y)/(float)(right_arm_y-fold_oy);
for (w=0;w < canvas->w;w+=0.5)
for(h=0;h < canvas->h;h+=0.5)
{
dist_x=right_step_x*w+left_step_x*h;
dist_y=right_step_y*w+left_step_y*h;
api->putpixel(canvas, x-dist_x, y-dist_y, api->getpixel(temp,w,h));
}
// Erasing the triangle.
// The 1 pixel in plus is a workaround for api-line not getting the end in some lines.
if (left_arm_x > canvas->w)
{
left_y=(float)right_arm_y/left_arm_x*(left_arm_x-canvas->w);
for (h = 0; h <= right_arm_y; h++)
api->line((void *)api, which, canvas, snapshot, canvas->w, left_y-h, -1, right_arm_y-h, 1, fold_erase);
}
else if (right_arm_y > canvas->h)
{
right_x=(float)left_arm_x/right_arm_y*(right_arm_y-canvas->h);
for (w = 0; w <= left_arm_x; w++)
api->line((void *)api, which, canvas, snapshot, left_arm_x-w, 0, right_x-w, canvas->h +1, 1, fold_erase);
}
else
for (w = 0; w <= min(left_arm_x,right_arm_y); w++) // The -1 values are because api->line
api->line((void *)api, which, canvas, snapshot, left_arm_x-w, 0, -1, right_arm_y-w, 1, fold_erase);
SDL_BlitSurface(canvas,0,temp,0);
// Shadows
if (left_arm_x > canvas->w)
{
for (fold_shadow_value = 0; fold_shadow_value < 40; fold_shadow_value+=1)
api->line((void *)api, which, canvas, temp, canvas->w, left_y-fold_shadow_value, 0, right_arm_y-fold_shadow_value, 1, fold_shadow);
}
else if (right_arm_y > canvas->h)
{
for (fold_shadow_value = 0; fold_shadow_value < 40; fold_shadow_value+=1)
api->line((void *)api, which, canvas, temp, left_arm_x-fold_shadow_value, 0, right_x - fold_shadow_value, canvas->h, 1, fold_shadow);
}
else
for (fold_shadow_value = 0; fold_shadow_value < 40; fold_shadow_value+=1)
api->line((void *)api, which, canvas, temp, left_arm_x-fold_shadow_value, 0, 0, right_arm_y-fold_shadow_value, 1, fold_shadow);
SDL_BlitSurface(canvas,0,temp,0);
for (fold_shadow_value = 0; fold_shadow_value < 40; fold_shadow_value+=1)
{
dist_x=fold_shadow_value*(right_step_x+left_step_x);
dist_y=fold_shadow_value*(right_step_y+left_step_y);
api->line((void *)api, which, canvas, temp, left_arm_x+fold_shadow_value*right_step_x, fold_shadow_value*right_step_y, fold_shadow_value*left_step_x, right_arm_y+fold_shadow_value*left_step_y, 1, fold_shadow);
}
api->line((void *)api, which, canvas, snapshot, x, y, right_arm_x, right_arm_y, 1, fold_print_line);
api->line((void *)api, which, canvas, snapshot, x, y, left_arm_x, left_arm_y, 1, fold_print_line);
api->line((void *)api, which, canvas, snapshot, left_arm_x, left_arm_y, right_arm_x, right_arm_y, 1, fold_print_dark_line);
}
SDL_Surface * rotate(magic_api * api, SDL_Surface * canvas, int angle)
{
SDL_Surface * temp;
int x,y;
int a,b;
if (angle==180)
temp=SDL_CreateRGBSurface(SDL_ANYFORMAT, canvas->w, canvas->h, canvas->format->BitsPerPixel,
canvas->format->Rmask, canvas->format->Gmask, canvas->format->Bmask, canvas->format->Amask);
else
temp=SDL_CreateRGBSurface(SDL_ANYFORMAT, canvas->h, canvas->w, canvas->format->BitsPerPixel,
canvas->format->Rmask, canvas->format->Gmask, canvas->format->Bmask, canvas->format->Amask);
switch (angle)
{
case 90:
for (x=0; x<canvas->w; x++)
for (y=0; y<canvas->h; y++)
{
translate_xy(canvas,x,y,&a,&b,90);
api->putpixel(temp,a,b,api->getpixel(canvas, x, y));
}
break;
case 180:
// printf("%i, %i\n",temp,canvas);
for (x=0; x<canvas->w; x++)
for (y=0; y<canvas->h; y++)
{
translate_xy(canvas,x,y,&a,&b,180);
api->putpixel(temp,a,b,api->getpixel(canvas, x, y));
}
break;
case 270:
for (x=0; x<canvas->w; x++)
for (y=0; y<canvas->h; y++)
{
translate_xy(canvas,x,y,&a,&b,270);
api->putpixel(temp,a,b,api->getpixel(canvas, x, y));
}
break;
}
return temp;
}
void translate_coords(SDL_Surface * canvas,int angle)
{
int a,b;
switch (angle)
{
case 90:
translate_xy(canvas,right_arm_x,right_arm_y,&a,&b,90);
right_arm_x=a;
right_arm_y=b;
translate_xy(canvas,left_arm_x,left_arm_y,&a,&b,90);
left_arm_x=a;
left_arm_y=b;
break;
case 180:
right_arm_x=canvas->w-1-right_arm_x;
right_arm_y=canvas->h-1-right_arm_y;
left_arm_x=canvas->w-1-left_arm_x;
left_arm_y=canvas->h-1-left_arm_y;
break;
case 270:
translate_xy(canvas,right_arm_x,right_arm_y,&a,&b,270);
right_arm_x=a;
right_arm_y=b;
translate_xy(canvas,left_arm_x, left_arm_y, &a, &b, 270);
left_arm_x=a;
left_arm_y=b;
break;
}
}
void translate_xy(SDL_Surface * canvas, int x, int y, int * a, int * b, int rotation)
{
switch (rotation)
{
case 90:
*a=y;
*b=canvas->w -1 -x;
break;
case 180:
*a=canvas->w -1 -x;
*b=canvas->h -1 -y;
break;
case 270:
*a=canvas->h -1 -y;
*b=x;
break;
}
}
void fold_release(magic_api * api, int which,
SDL_Surface * canvas, SDL_Surface * snapshot,
int x, int y, SDL_Rect * update_rect)
{
int a,b;
SDL_Surface * temp, *temp2;
x=fold_x;
y=fold_y;
fold_ox=fold_oy=0;
SDL_BlitSurface(snapshot, 0, canvas, 0);
switch (corner)
{
case 1:
translate_xy(canvas,x,y,&a,&b,90);
translate_coords(canvas,90);
temp=rotate(api, canvas, 90);
fold_draw (api, which, temp, snapshot, a, b,update_rect);
temp2=rotate(api,temp,270);
SDL_BlitSurface(temp2,0,canvas,0);
SDL_FreeSurface(temp);
SDL_FreeSurface(temp2);
break;
case 2:
fold_draw (api, which, canvas, snapshot, x,y,update_rect);
break;
case 3:
translate_xy(canvas,x,y,&a,&b,270);
translate_coords(canvas,270);
temp=rotate(api, canvas, 270);
fold_draw (api, which, temp, snapshot, a, b,update_rect);
temp2=rotate(api,temp,90);
SDL_BlitSurface(temp2,0,canvas,0);
SDL_FreeSurface(temp);
SDL_FreeSurface(temp2);
break;
case 4:
translate_xy(canvas,x,y,&a,&b,180);
translate_coords(canvas,180);
temp=rotate(api, canvas, 180);
fold_draw (api, which, temp, snapshot, a, b,update_rect);
temp2=rotate(api,temp,180);
SDL_BlitSurface(temp2,0,canvas,0);
SDL_FreeSurface (temp);
SDL_FreeSurface (temp2);
break;
}
update_rect->x=update_rect->y=0;
update_rect->w=canvas->w;
update_rect->h=canvas->h;
}
void fold_shutdown(magic_api * api)
@ -93,36 +350,6 @@ inline Uint8 fold_what_corner(int x, int y, SDL_Surface * canvas)
}
}
void static fold_rotate(void * ptr, SDL_Surface * canvas, SDL_Surface * snapshot, Uint8 corner)
{
magic_api * api = (magic_api *) ptr;
unsigned int x,y;
if ((corner==2) || (corner==4)) //rotate +90 degs
{
for (x = 0; x<FOLD_LEN; x++)
for (y =0; y<FOLD_LEN; y++)
api->putpixel(canvas, x, y, api->getpixel(snapshot, y, FOLD_LEN-x));
}
else //rotate -90 degs
{
for (x=0; x<FOLD_LEN; x++)
for (y=0; y<FOLD_LEN; y++)
api->putpixel(canvas,x,y,api->getpixel(snapshot,FOLD_LEN-y,x));
}
}
void static fold_flip(void * ptr, SDL_Surface * canvas, SDL_Surface * snapshot, Uint8 corner) //flip page
{
magic_api * api = (magic_api *) ptr;
unsigned int x, y;
for (x=0; x<snapshot->w; x++)
for (y=0; y<snapshot->h; y++)
api->putpixel(canvas, x, y, api->getpixel(snapshot, snapshot->w-x, y)); //flip horizontal
}
static void fold_print_line(void * ptr, int which, SDL_Surface * canvas, SDL_Surface * last,
int x, int y)
@ -130,126 +357,115 @@ static void fold_print_line(void * ptr, int which, SDL_Surface * canvas, SDL_Sur
magic_api * api = (magic_api *) ptr;
api->putpixel(canvas, x, y, SDL_MapRGB(last->format, 222, 222, 222)); //Middle gray. Color have been set arbitrary.
}
static void fold_print_dark_line(void * ptr, int which, SDL_Surface * canvas, SDL_Surface * last,
int x, int y)
{
magic_api * api = (magic_api *) ptr;
api->putpixel(canvas, x, y, SDL_MapRGB(last->format, 90, 90, 90)); //It should not look too black nor too white with shadowed colors.
}
static void fold_erase(void * ptr, int which, SDL_Surface * canvas, SDL_Surface * last,
int x, int y)
{
magic_api * api = (magic_api *) ptr;
api->putpixel(canvas, x, y, fold_color);
}
static void fold_draw_triangle (magic_api * ptr, int which, SDL_Surface * canvas, SDL_Surface * snapshot, Uint8 corner)
{
magic_api * api = (magic_api *) ptr;
unsigned int i;
//this function could be optimized but it would make this code less readable
switch(corner) //corners in mathematical order: 1: right upper, 2: left upper, ...
{
case 1:
for (i = 0; i < FOLD_LEN; i++)
api->line((void *)api, which, canvas, snapshot, canvas->w-FOLD_LEN+i, 0, canvas->w, FOLD_LEN-i, 1, fold_erase);
//clear the triangle by the corner
api->line((void *)api, which, canvas, snapshot,canvas->w-FOLD_LEN, 0, canvas->w-FOLD_LEN, FOLD_LEN, 1, fold_print_line);
//draw vertical line
api->line((void *)api, which, canvas, snapshot,canvas->w-FOLD_LEN, FOLD_LEN, canvas->w, FOLD_LEN, 1, fold_print_line);
//draw horizontal line
api->line((void *)api, which, canvas, snapshot,canvas->w-FOLD_LEN, 0, canvas->w, FOLD_LEN, 1, fold_print_line);
//and another: oblique
break;
case 2:
for (i = 0; i < FOLD_LEN; i++)
api->line((void *)api, which, canvas, snapshot, 0, FOLD_LEN-i, FOLD_LEN-i, 0, 1, fold_erase);
//sequence just like above
api->line((void *)api, which, canvas, snapshot,FOLD_LEN, 0, FOLD_LEN, FOLD_LEN, 1, fold_print_line);
api->line((void *)api, which, canvas, snapshot,0, FOLD_LEN, FOLD_LEN, FOLD_LEN, 1, fold_print_line);
api->line((void *)api, which, canvas, snapshot,0, FOLD_LEN, FOLD_LEN, 0, 1, fold_print_line);
break;
case 3:
for (i = 0; i < FOLD_LEN; i++)
api->line((void *)api, which, canvas, snapshot, 0, canvas->h-FOLD_LEN+i, FOLD_LEN-i, canvas->h, 1, fold_erase);
api->line((void *)api, which, canvas, snapshot,FOLD_LEN, canvas->h-FOLD_LEN, FOLD_LEN, canvas->h, 1, fold_print_line);
api->line((void *)api, which, canvas, snapshot,0, canvas->h-FOLD_LEN, FOLD_LEN, canvas->h-FOLD_LEN, 1, fold_print_line);
api->line((void *)api, which, canvas, snapshot,0, canvas->h-FOLD_LEN, FOLD_LEN, canvas->h, 1, fold_print_line);
break;
case 4:
for (i = 0; i < FOLD_LEN; i++)
api->line((void *)api, which, canvas, snapshot, canvas->w-FOLD_LEN+i, canvas->h, canvas->w,
canvas->h-FOLD_LEN+i, 1, fold_erase);
api->line((void *)api, which, canvas, snapshot,canvas->w-FOLD_LEN, canvas->h-FOLD_LEN, canvas->w-FOLD_LEN,
canvas->h, 1, fold_print_line);
api->line((void *)api, which, canvas, snapshot,canvas->w-FOLD_LEN, canvas->h-FOLD_LEN, canvas->w,
canvas->h-FOLD_LEN, 1, fold_print_line);
api->line((void *)api, which, canvas, snapshot,canvas->w-FOLD_LEN, canvas->h, canvas->w, canvas->h-FOLD_LEN, 1, fold_print_line);
break;
}
api->putpixel(canvas, x, y, SDL_MapRGB(canvas->format, fold_r, fold_g, fold_b));
}
void fold_click(magic_api * ptr, int which, int mode,
SDL_Surface * canvas, SDL_Surface * snapshot,
int x, int y, SDL_Rect * update_rect)
SDL_Surface * canvas, SDL_Surface * snapshot,
int x, int y, SDL_Rect * update_rect)
{
Uint8 corner;
magic_api * api = (magic_api *) ptr;
corner=fold_what_corner(x, y, snapshot);
magic_api * api = (magic_api *) ptr;
corner=fold_what_corner(x, y, snapshot);
fold_color=SDL_MapRGB(snapshot->format, fold_r, fold_g, fold_b);
switch (corner)
{
case 1:
fold_ox=canvas->w-1;
fold_oy=0;
break;
case 2:
fold_ox=fold_oy=0;
break;
case 3:
fold_ox=0;
fold_oy=canvas->h-1;
break;
case 4:
fold_ox=canvas->w-1;
fold_oy=canvas->h-1;
break;
}
fold_surface_src= SDL_CreateRGBSurface(SDL_ANYFORMAT, FOLD_LEN, FOLD_LEN, snapshot->format->BitsPerPixel,
snapshot->format->Rmask, snapshot->format->Gmask, snapshot->format->Bmask, snapshot->format->Amask);
fold_drag(api, which, canvas, snapshot, x, y, x, y, update_rect);
}
fold_surface_dst=SDL_CreateRGBSurface(SDL_ANYFORMAT, FOLD_LEN, FOLD_LEN, snapshot->format->BitsPerPixel,
snapshot->format->Rmask, snapshot->format->Gmask, snapshot->format->Bmask, snapshot->format->Amask);
switch(corner)
{
case 1: //Right Upper
update_rect->x=canvas->w-FOLD_LEN;
update_rect->y=0;
break;
void fold_preview(magic_api * api, int which, SDL_Surface * canvas,
SDL_Surface * snapshot, int ox, int oy, int x, int y,
SDL_Rect * update_rect)
{
int middle_point_x;
int middle_point_y;
case 2: //LU
update_rect->x=update_rect->y=0;
break;
fold_x=x;
fold_y=y;
SDL_BlitSurface(snapshot,0,canvas,0);
middle_point_x=(fold_ox+x)/2;
middle_point_y=(fold_oy+y)/2;
switch(corner)
{
case 1: //Right Upper
right_arm_x=fold_ox- (fold_ox-middle_point_x)-middle_point_y*middle_point_y/(fold_ox-middle_point_x);
right_arm_y=fold_oy;
left_arm_x=fold_ox;
left_arm_y=fold_oy-(fold_oy-middle_point_y)-(fold_ox-middle_point_x)*(fold_ox-middle_point_x)/(fold_oy-middle_point_y);
break;
case 2: //LU
right_arm_x=fold_ox;
right_arm_y=middle_point_y+middle_point_x*middle_point_x/middle_point_y;
left_arm_x=middle_point_x+middle_point_y*middle_point_y/middle_point_x;
left_arm_y=fold_oy;
break;
case 3: //LL
update_rect->x=0;
update_rect->y=canvas->h-FOLD_LEN;
break;
case 3: //LL
right_arm_x=middle_point_x+(fold_oy-middle_point_y)*(fold_oy-middle_point_y)/middle_point_x;
right_arm_y=fold_oy;
case 4: //RL
update_rect->x=canvas->w-FOLD_LEN;
update_rect->y=canvas->h-FOLD_LEN;
break;
}
update_rect->w=FOLD_LEN;
update_rect->h=FOLD_LEN;
SDL_BlitSurface(snapshot, update_rect, fold_surface_src, NULL);
fold_flip(api, fold_surface_dst, fold_surface_src, corner);
SDL_BlitSurface(fold_surface_dst, NULL, canvas, update_rect);
left_arm_x=fold_ox;
left_arm_y=fold_oy-(fold_oy-middle_point_y)-(fold_ox-middle_point_x)*(fold_ox-middle_point_x)/(fold_oy-middle_point_y);
break;
SDL_BlitSurface(canvas, update_rect, fold_surface_src, NULL);
fold_rotate(api, fold_surface_dst, fold_surface_src, corner);
SDL_BlitSurface(fold_surface_dst, NULL, canvas, update_rect);
fold_draw_triangle (api, which, canvas, snapshot, corner);
case 4: //RL
right_arm_x=fold_ox;
right_arm_y=fold_oy-(fold_oy-middle_point_y)-(fold_ox-middle_point_x)*(fold_ox-middle_point_x)/(fold_oy-middle_point_y);
left_arm_x=fold_ox-(fold_ox-middle_point_x)-(fold_oy-middle_point_y)*(fold_oy-middle_point_y)/(fold_ox-middle_point_x);
left_arm_y=fold_oy;
break;
}
api->line((void *)api, which, canvas, snapshot, x, y, right_arm_x, right_arm_y, 1, fold_print_line);
api->line((void *)api, which, canvas, snapshot, x, y, left_arm_x, left_arm_y, 1, fold_print_line);
api->line((void *)api, which, canvas, snapshot, left_arm_x, left_arm_y, right_arm_x, right_arm_y, 1, fold_print_line);
update_rect->x=update_rect->y=0;
update_rect->w=canvas->w;
update_rect->h=canvas->h;
}
void fold_drag(magic_api * api, int which, SDL_Surface * canvas,
SDL_Surface * snapshot, int ox, int oy, int x, int y,
SDL_Rect * update_rect)
{
// Avoid division by zero when calculating the preview
x=clamp(2,x,canvas->w-2);
y=clamp(2,y,canvas->h-2);
fold_preview(api, which, canvas, snapshot, ox, oy, x, y, update_rect);
}
void fold_switchin(magic_api * api, int which, int mode, SDL_Surface * canvas)