skin_engine: ease the restrictions on %x/%xl

%x and %xl only require the id and filename now.
If you leave off the x,y it will default to 0,0.
If you want to use the default x,y you can still put in the
num_subimages param on the end (e.g %xl(a, file, 3) )

Change-Id: I8eff793dfdd037e302ace8deec9dc16dcea264a7

apps/gui/skin_engine/skin_parser.c

@@ -387,19 +387,30 @@ static int parse_image_load(struct skin_element *element,
 {
     const char* filename;
     const char* id;
-    int x,y;
+    int x = 0,y = 0, subimages = 1;
     struct gui_img *img;
 
-    /* format: %x(n,filename.bmp,x,y)
+    /* format: %x(n,filename.bmp[,x,y])
-       or %xl(n,filename.bmp,x,y)
+       or %xl(n,filename.bmp[,x,y])
-       or %xl(n,filename.bmp,x,y,num_subimages)
+       or %xl(n,filename.bmp[,x,y,num_subimages])
     */
 
     id = get_param_text(element, 0);
     filename = get_param_text(element, 1);
-    x = get_param(element, 2)->data.number;
+    /* x,y,num_subimages handling:
-    y = get_param(element, 3)->data.number;
+     * If all 3 are left out use sane defaults.
-
+     * If there are 2 params it must be x,y
+     * if there is only 1 param it must be the num_subimages
+     */
+    if (element->params_count == 3)
+        subimages = get_param(element, 2)->data.number;
+    else if (element->params_count > 3)
+    {
+        x = get_param(element, 2)->data.number;
+        y = get_param(element, 3)->data.number;
+        if (element->params_count == 5)
+            subimages = get_param(element, 4)->data.number;
+    }
     /* check the image number and load state */
     if(skin_find_item(id, SKIN_FIND_IMAGE, wps_data))
     {
@@ -414,7 +425,7 @@ static int parse_image_load(struct skin_element *element,
     img->label = PTRTOSKINOFFSET(skin_buffer, (void*)id);
     img->x = x;
     img->y = y;
-    img->num_subimages = 1;
+    img->num_subimages = subimages;
     img->display = -1;
     img->using_preloaded_icons = false;
     img->buflib_handle = -1;
@@ -423,15 +434,7 @@ static int parse_image_load(struct skin_element *element,
     img->vp = PTRTOSKINOFFSET(skin_buffer, &curr_vp->vp);
 
     if (token->type == SKIN_TOKEN_IMAGE_DISPLAY)
-    {
         token->value.data = PTRTOSKINOFFSET(skin_buffer, img);
-    }
-    else if (element->params_count == 5)
-    {
-        img->num_subimages = get_param(element, 4)->data.number;
-        if (img->num_subimages <= 0)
-            return WPS_ERROR_INVALID_PARAM;
-    }
 
     if (!strcmp(img->bm.data, "__list_icons__"))
     {

lib/skin_parser/tag_table.c

@@ -176,9 +176,9 @@ static const struct tag_info legal_tags[] =
     { SKIN_TOKEN_DISABLE_THEME,         "wd", "", 0|NOBREAK },
     { SKIN_TOKEN_DRAW_INBUILTBAR,       "wi", "", SKIN_REFRESH_STATIC|NOBREAK },
     
-    { SKIN_TOKEN_IMAGE_PRELOAD,         "xl", "SFII|I", 0|NOBREAK },
+    { SKIN_TOKEN_IMAGE_PRELOAD,         "xl", "SF|III", 0|NOBREAK },
     { SKIN_TOKEN_IMAGE_PRELOAD_DISPLAY, "xd", "S|[IT]I", 0 },
-    { SKIN_TOKEN_IMAGE_DISPLAY,         "x", "SFII", SKIN_REFRESH_STATIC|NOBREAK },
+    { SKIN_TOKEN_IMAGE_DISPLAY,         "x", "SF|II", SKIN_REFRESH_STATIC|NOBREAK },
     
     { SKIN_TOKEN_LOAD_FONT,             "Fl" , "IF|I", 0|NOBREAK },
     { SKIN_TOKEN_ALBUMART_LOAD,         "Cl" , "IIII|ss", 0|NOBREAK },

manual/appendix/wps_tags.tex

@@ -369,19 +369,19 @@ Examples:
         & Load and set a backdrop image for the WPS.
           This image must be exactly the same size as your LCD.\\
     }%
-    \config{\%x(n,filename,x,y)}
+    \config{\%x(n,filename[,x,y])}
         & Load and display an image\newline
           \config{n}: image ID (a-z and A-Z) for later referencing in \config{\%xd}\newline
           \config{filename}: file name relative to \fname{/.rockbox/} and including ``.bmp''\newline
-          \config{x}: x coordinate\newline
+          \config{x}: x coordinate (defaults to 0 if both x and y are not specified)\newline
-          \config{y}: y coordinate.\\
+          \config{y}: y coordinate. (defaults to 0 if both x and y are not specified)\\
-    \config{\%xl(n,filename,x,y,\tabnlindent[nimages])}
+    \config{\%xl(n,filename,[x,y],\tabnlindent[nimages])}
         & Preload an image for later display (useful for when your images are displayed conditionally).\newline
           \config{n}: image ID (a-z and A-Z) for later referencing in \config{\%xd}\newline
           \config{filename}: file name relative to \fname{/.rockbox/} and including ``.bmp''\newline
             If the filename is ``\_\_list\_icons\_\_'' the list icon bitmap will be used instead\newline
-          \config{x}: x coordinate\newline
+          \config{x}: x coordinate (defaults to 0 if both x and y are not specified)\newline
-          \config{y}: y coordinate\newline
+          \config{y}: y coordinate. (defaults to 0 if both x and y are not specified)\\
           \config{nimages}: (optional) number of sub-images (tiled vertically, of the same height)
           contained in the bitmap. Default is 1.\\
     \config{\%xd(n[i] [,tag] [,offset])} & Display a preloaded image.