Prerequestite libraries: OSlib

/* By Johnathan Coxhead - released onto the net 23/7/96 */
 #ifndef spritefile_H
 #define spritefile_H
 #ifndef types_H
 #include "types.h"
 #endif
 #ifndef os_H
 #include "os.h"
 #endif
 #ifndef osspriteop_H
 #include "osspriteop.h"
 #endif
 #define spritefile_NARROW_ENTRIES 0x1u
 /*************************
 * Function declarations *
 *************************/
 #ifdef __cplusplus
 extern "C" {
 #endif
 /* ------------------------------------------------------------------------
 * Function: spritefile_render()
 */
 extern void spritefile_render (bits flags,
	 osspriteop_header const *sprite,
	 int size,
	 os_trfm const *trfm,
	 os_box const *clip);
 /* ------------------------------------------------------------------------
 * Function: spritefile_bbox()
 */
 extern void spritefile_bbox (bits flags,
	 osspriteop_header const *sprite,
	 int size,
	 os_trfm const *trfm,
	 os_box *bbox);
 /* ------------------------------------------------------------------------
 * Function: spritefile_declare_fonts()
 */
 extern void spritefile_declare_fonts (bits flags,
	 osspriteop_header const *sprite,
	 int size);
 #ifdef __cplusplus
 }
 #endif
 #endif

---

/* By Johnathan Coxhead - released onto the net 23/7/96 */
 #include "colourtrans.h"
 #include "draw.h"
 #include "os.h"
 #include "osspriteop.h"
 #include "wimp.h"
 #include "x.h"
 #include "spritefile.h"
 #include "trfm.h"
 x_LOCAL_ERROR (Bad_Mode, 1, "Bad mode")
 void spritefile_render (bits flags, osspriteop_header const *sprite,
	 int size, os_trfm const *trfm, os_box const *clip)
 { osspriteop_trans_tab *table;
 bool narrow_entries = (flags & spritefile_NARROW_ENTRIES) != NONE;
 os_PALETTE (20) palette;
 int log2_bpp;
 if ((sprite->image - sizeof (osspriteop_header))/sizeof (os_colour_pair)
	 == 0)
 { if ((os_read_mode_variable (sprite->mode, os_MODEVAR_LOG2_BPP,
	 &log2_bpp) & _C) != NONE)
	 x_THROW (Bad_Mode);
	 if (log2_bpp < 3)
	 wimp_read_true_palette ((os_palette *) &palette);
	 switch (log2_bpp)
	 { case 0:
	 palette.entries [1] = palette.entries [7];
	 break;
	 case 1:
	 palette.entries [1] = palette.entries [2];
	 palette.entries [2] = palette.entries [4];
	 palette.entries [3] = palette.entries [7];
	 break;
	 }
	 colourtrans_generate_table
	 ( sprite->mode,
	 log2_bpp < 3?
		 (os_palette *) &palette:
		 colourtrans_CURRENT_PALETTE,
	 colourtrans_CURRENT_MODE,
	 colourtrans_CURRENT_PALETTE,
	 table = x_ALLOC
	 ( colourtrans_generate_table
	 ( sprite->mode,
		 log2_bpp < 3?
			(os_palette *) &palette:
			colourtrans_CURRENT_PALETTE,
		 colourtrans_CURRENT_MODE,
		 colourtrans_CURRENT_PALETTE,
		 NULL,
		 colourtrans_GIVEN_SPRITE |
			(narrow_entries? NONE: colourtrans_RETURN_WIDE_ENTRIES),
		 SKIP,
		 SKIP
	 )
	 ),
	 colourtrans_GIVEN_SPRITE |
		 (narrow_entries? NONE: colourtrans_RETURN_WIDE_ENTRIES),
	 SKIP,
	 SKIP
	 );
 }
 else
	 colourtrans_generate_table_for_sprite
	 ( osspriteop_UNSPECIFIED,
	 (osspriteop_id) sprite,
	 colourtrans_CURRENT_MODE,
	 colourtrans_CURRENT_PALETTE,
	 table = x_ALLOC
	 ( colourtrans_generate_table_for_sprite
	 ( osspriteop_UNSPECIFIED,
		 (osspriteop_id) sprite,
		 colourtrans_CURRENT_MODE,
		 colourtrans_CURRENT_PALETTE,
		 NULL,
		 colourtrans_GIVEN_SPRITE |
			(narrow_entries? NONE: colourtrans_RETURN_WIDE_ENTRIES),
		 SKIP,
		 SKIP
	 )
	 ),
	 colourtrans_GIVEN_SPRITE |
		 (narrow_entries? NONE: colourtrans_RETURN_WIDE_ENTRIES),
	 SKIP,
	 SKIP
	 );
 osspriteop_put_sprite_trfm (osspriteop_PTR, osspriteop_UNSPECIFIED,
	 (osspriteop_id) sprite, NONE, NULL,
	 os_ACTION_USE_MASK |
		 (narrow_entries? NONE: osspriteop_GIVEN_WIDE_ENTRIES),
	 trfm, table);
 x_FREE (table, 0);
 }
 void spritefile_bbox (bits flags, osspriteop_header const *sprite,
	 int size, os_trfm const *trfm, os_box *bbox)
 { os_box box;
 os_mode mode;
 int width, height, xeig, yeig;
 /*Get bbox of sprite into box.*/
 osspriteop_read_sprite_size (osspriteop_PTR, osspriteop_UNSPECIFIED,
	 (osspriteop_id) sprite, &width, &height, NULL, &mode);
 if ((os_read_mode_variable (mode, os_MODEVAR_XEIG_FACTOR, &xeig) &
	 _C) != NONE || (os_read_mode_variable (mode,
	 os_MODEVAR_YEIG_FACTOR, &yeig) & _C) != NONE)
	 x_THROW (Bad_Mode);
 box.x0 = box.y0 = 0;
 box.x1 = (width << xeig)*draw_OS_UNIT;
 box.y1 = (height << yeig)*draw_OS_UNIT;
 trfm_box (bbox, trfm, &box);
 }
 void spritefile_declare_fonts (bits flags,
	 osspriteop_header const *sprite, int size)
 { NOT_USED (flags)
 NOT_USED (sprite)
 NOT_USED (size)
 }
 ----------------------------------------------------------------------------
 Trfm_box() just transforms a box and rebounds it:
 ----------------------------------------------------------------------------
 void trfm_box (os_box *b, os_trfm const *m, os_box const *b1)
 /*set |b| to the bbox of |b1| after transformation by |m|.*/
 { os_coord c [4], c1 [4];
 int i;
 /*Get the four corners of |b1|.*/
 c1 [0].x = b1->x0, c1 [0].y = b1->y0;
 c1 [1].x = b1->x1, c1 [1].y = b1->y0;
 c1 [2].x = b1->x1, c1 [2].y = b1->y1;
 c1 [3].x = b1->x0, c1 [3].y = b1->y1;
 /*Transform them all.*/
 for (i = 0; i < 4; i++)
	 trfm_point (&c [i], m, &c1 [i]);
 /*Bound the four new points.*/
 b->x0 = b->y0 = INT_MAX;
 b->x1 = b->y1 =-INT_MAX;
 for (i = 0; i < 4; i++)
 { (void) MINAB (b->x0, c [i].x);
	 (void) MINAB (b->y0, c [i].y);
	 (void) MAXAB (b->x1, c [i].x);
	 (void) MAXAB (b->y1, c [i].y);
 } }