mdw@git.distorted.org.uk Git - ssr/blob - StraySrc/Libraries/Steel/c/pointer

   1 /*
   2  * pointer.c
   3  *
   4  * Handling of pointer-shape changing
   5  *
   6  * © 1994-1998 Straylight
   7  */
   8
   9 /*----- Licensing note ----------------------------------------------------*
  10  *
  11  * This file is part of Straylight's Steel library.
  12  *
  13  * Steel is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2, or (at your option)
  16  * any later version.
  17  *
  18  * Steel is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with Steel.  If not, write to the Free Software Foundation,
  25  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  26  */
  27
  28 #include <stdio.h>
  29
  30 #include "os.h"
  31 #include "sprite.h"
  32 #include "swis.h"
  33 #include "wimpt.h"
  34 #include "pointer.h"
  35
  36 static BOOL pointer__notDefault;
  37
  38 /*
  39  * os_error *pointer__magicSpriteOp(sprite_area *a,
  40  *                                  sprite _id *sid,
  41  *                                  os_regset *r)
  42  *
  43  * Use
  44  *  Performs a sprite op of the appropriate kind for the sprite area given.
  45  *
  46  * Parameters
  47  *  sprite_area *a == the sprite area to do the op on
  48  *  sprite_id *sid == the sprite id to do it to
  49  *  os_regset r == other registers for the op
  50  *
  51  * Returns
  52  *  An error or 0.
  53  */
  54
  55 static os_error *pointer__magicSpriteOp(sprite_area *a,
  56                                         sprite_id *sid,
  57                                         os_regset *r)
  58 {
  59   if (a==(sprite_area *)1)
  60   {
  61     /* --- The WIMP sprite area --- */
  62
  63     r->r[0]&=~0x300;
  64     r->r[2]=(int)sid->s.name;
  65     return (os_swix(XWimp_SpriteOp,r));
  66   }
  67   else if (!a)
  68   {
  69     /* --- The nasty system sprite area --- */
  70
  71     r->r[0]&=~0x300;
  72     r->r[2]=(int)sid->s.name;
  73     return (os_swix(XOS_SpriteOp,r));
  74   }
  75   else
  76   {
  77     /* --- A nice user sprite area --- */
  78
  79     r->r[0]&=~0x300;
  80     if (sid->tag)
  81     {
  82       r->r[0]|=0x200;
  83       r->r[2]=(int)sid->s.addr;
  84     }
  85     else
  86     {
  87       r->r[0]|=0x100;
  88       r->r[2]=(int)sid->s.name;
  89     }
  90     r->r[1]=(int)a;
  91
  92     return (os_swix(XOS_SpriteOp,r));
  93   }
  94 }
  95
  96 /*
  97  * BOOL pointer__spriteExist(sprite_area *a,char *name)
  98  *
  99  * Use
 100  *  Returns whether a named sprite exists in the given area
 101  *
 102  * Parameters
 103  *  sprite_area *a == the sprite area
 104  *  char *name == the name of the sprite to test
 105  *
 106  * Returns
 107  *  TRUE if the sprite is there
 108  */
 109
 110 static BOOL pointer__spriteExist(sprite_area *a,char *name)
 111 {
 112   os_regset r;
 113   sprite_id sid;
 114
 115   sid.s.name=name;
 116   sid.tag=0;
 117
 118   r.r[0]=40;
 119   return (!pointer__magicSpriteOp(a,&sid,&r));
 120 }
 121
 122 /*
 123  * os_error *pointer_set_shape(sprite_area *a,sprite_id *sid,int x,int y)
 124  *
 125  * Use
 126  *  Sets the pointer shape to be the pointer specified.  If a pointer with
 127  *  name `name<dx><dy>' is found in the sprite area, that's used instead, and
 128  *  the active point is scaled assuming that the original was specified in
 129  *  mode-8 type coordinates.
 130  *
 131  * Parameters
 132  *  sprite_area *a == the sprite area containing the sprite
 133  *  sprite_id *sid == pointer to the sprite identifier (dumb idea)
 134  *  int x,int y == coordinates (in pixels) of the hot-spot
 135  */
 136
 137 os_error *pointer_set_shape(sprite_area *a,sprite_id *sid,int x,int y)
 138 {
 139   char buffer[15];
 140   sprite_id s;
 141   os_regset r;
 142
 143   if (!sid->tag)
 144   {
 145     /* --- Try and find a good match for the mode --- */
 146
 147     sprintf(buffer,"%s%i%i",sid->s.name,wimpt_dx(),wimpt_dy());
 148     if (pointer__spriteExist(a,buffer))
 149     {
 150       s.s.name=buffer;
 151       s.tag=0;
 152       sid=&s;
 153       x=(x*2)/wimpt_dx();
 154       y=(y*4)/wimpt_dy();
 155     }
 156   }
 157
 158   /* --- Now set up the pointer shape --- */
 159
 160   r.r[0]=36;
 161   r.r[3]=2;                     /* Set everything up as nicely as possible */
 162   r.r[4]=x;
 163   r.r[5]=y;
 164   r.r[6]=r.r[7]=0;              /* No translation table, no zoom box       */
 165   pointer__notDefault=TRUE;
 166   return (pointer__magicSpriteOp(a,sid,&r));
 167 }
 168
 169 /*
 170  * void pointer_reset_shape(void)
 171  *
 172  * Use
 173  *  Resets the pointer shape
 174  */
 175
 176 void pointer_reset_shape(void)
 177 {
 178   if (pointer__notDefault)
 179     os_cli("%pointer");
 180   pointer__notDefault=FALSE;
 181 }