Pal set
Syntax
INT pal_set ( [<INT paletteID>] , <INT first_color> , <INT num_colors> , <POINTER palette_data>)
Description
Changes the color palette of an 8 bit (256 color) graphic, with the palette that is loaded with Pal_load(). This palette can also be loaded from MAP's, FPG's, FNT's and other image formats, provided that they are 8 bit images. Unlike Pal_map_assign(), the change is not immediately visible, and the function Pal_refresh() has to be called afterwards to make the change visible. The difference however, is that it not replaces the whole palette, but allows a specified number of colors to be changed, so it's a bit more flexible.
Also called colors_set(). The previous name set_colors() is deprecated.
Parameters
| INT paletteID | - The handle of the color palette loaded with Pal_load(). This paramter is optional. |
| INT first_color | - The first color number of the palette. This doesn't necessarily have be the first color. |
| INT num_colors | - The number of colors you want to replace, wich counts from the first_color to the num_colors. See notes. |
| POINTER palette_data | - Pointer (Offset) to an array with the color values, that where obtained with Pal_get(). |
Note
The maximum number of colors cannot be bigger the 255. The num_colors starts counting from first_color, so if the first_color is 7, and num_colors is 7, the color value's 7-13 are changed. So logically, the value num_colors can only be 255 when first_color is 0. This range gives you all the colors. To be safe, the formula for the number of colors to modified is: num_colors-first_color.
I.e. num_colors: 55 - first_color: 4 = 51 colors are changed, the range from color index 4 up to color index 55.
Returns
INT : Error.
| 0 | - Error: could not open file; corrupt or truncated file; file doesn't contain palette information. |
| 1 | - No error: palette was set with success. |
Example
/* original bennupack example FROM: \2 Medium\fenix test\palettes\rbear8-2.prg (from bomberlink) */
/* this program demonstrates the use of the functions: pal_load(), pal_clone(), pal_get(), */
/* pal_map_assign(), pal_set() and pal_refresh(). */
IMPORT "mod_debug";
IMPORT "mod_say";
IMPORT "mod_map";
IMPORT "mod_key";
IMPORT "mod_video";
IMPORT "mod_text";
GLOBAL
// palette identifiers
int pal_orange;
int pal_green;
int pal_normal;
int status1;
int status2;
// identifier of the fpg archive
int fpg_id;
// arrays for the data of the two color palettes.
byte pal_orange_data[255];
byte pal_green_data[255];
int map_count;
PROCESS main();
BEGIN
set_fps(10,0);
set_mode(320,200,16); // we use a 16 bit color mode
// load two color palettes and duplicate one
pal_green=pal_load("rbear8-green.pal");
pal_orange=pal_load("rbear8-orange.pal");
// pal_clone (int pal_id);
pal_normal=pal_clone(pal_orange); // duplicate palette, i.e. make a copy of it.
// load the fpg file
fpg_id=fpg_load("rbear8.fpg");
write_int(0,10,10,0,&fps);
write(0,10,20,0,"F1/F2 - change palette");
x = 160;
y = 120;
// pal_get (int pal_id, int start_color, int num_colors, pointer pal_data);
pal_get(pal_green,7,7,&pal_green_data); // get colors 7 - 13 and store them in the array
pal_get(pal_orange,7,7,&pal_orange_data);
FROM map_count=1 TO 102; // there are 102 frames in the animation
// pal_map_assign (int fileid, int graph, int pal_id);
pal_map_assign(fpg_id,map_count,pal_normal); // assign the "normal (original source)" color
// palette that we duplicated earlier.
END
WHILE (NOT key(_ESC))
FROM graph=1 TO 13;
FRAME;
IF (key(_F1))
say("switched to green palette");
// pal_set (int pal_id, int start_color, int num_colors, pointer pal_data);
status1=pal_set(pal_normal,7,7,&pal_green_data); // change colors 7 - 13 in the "normal"
// palette, by using the values from the
// "green" color palette.
say("pal_set_status: "+status1);
// pal_refresh (int pal_id);
status2=pal_refresh(pal_normal); // apply the modified color palette to the graphics.
// this function is required to make the change visible.
say("pal_refresh_status: "+status2);
// conclusion: the difference between pal_map_assign() and pal_set() is that pal_map_assign()
// works immediately, and that pal_set() requires the palette to be refreshed to make the
// change visible.
END
IF (key(_F2))
say("switched to orange palette");
pal_set(pal_normal,7,7,&pal_orange_data); // colors 7 - 13
pal_refresh(pal_normal);
END
IF (key(_ESC))
BREAK;
END
END
END
END
Used in example: Pal_load(), pal_clone(), Pal_get(), Pal_map_assign(), Pal_refresh(), Say(), Set_fps(), Set_mode(), Write(), Write_int()
