doc@j.cc.purdue.edu (10/01/86)
From: wecker%cookie.DEC@decwrl.DEC.COM (DAVE TANSTAAFL WECKER)
Doc: Here is the source for a display program that can be used with the
image files that follow. I've been working with a Ray Tracing program,
and finally figured out how to take full advantage of the Amiga's
HAM (Hold and Modify) mode, yielding 4096 colors on the screen at
once.
If people like the pictures, I'll send more (they take from 1 hour
to several days on a dedicated VAX).
To use the program, compile and link it (nothing special needed) and
then type:
1> DISPLAY FOO.IMG
After the picture completes you can exit by clicking on the (invisible)
close gadget in the upper left corner. I know the program is (very)
rough, but I haven't had time to make it pretty.. just functional.
Please post it and let me know what you think.
Regards,
dave
--------------------Program begins below this line--------------------------
/***********************************************************************
*
* DISPLAY package for .img files (DBW encoding)
*
* File format:
* MAXX MAXY MAXCOLORS - header
* 256 hex colors in descending usage - colortable
* Encoding of pixels: (all printable ASCII)
* @ - O = Absolute color (low four bits) in color table
* P - _ = Relative color. Low four bits is new BLUE value
* ` - o = Relative color. Low four bits is new RED value
* p - DEL = Relative color. Low four bits is new GREEN value
* ' ' - > = Repeat introducer (next char - ' ' = repeat count)
* ? = Alternate encoding for <DEL>
* \r \n = Ignored (end of line markers) (NOT scan line)
*
* v1.0 860907 DBW
*
***********************************************************************/
#include <stdio.h>
#include <exec/types.h>
#include <intuition/intuition.h>
#include <intuition/intuitionbase.h>
#include <functions.h>
extern char *fgets();
#undef NULL
#define NULL ((void *)0)
#define CHECK(x) while (line[x] < ' ') {\
if (fgets(line,128,fp) == NULL) return(-1);\
x = 0;\
}
struct GfxBase *GfxBase;
struct IntuitionBase *IntuitionBase;
struct RastPort *rp;
struct ViewPort *vp;
struct Window *w;
struct Screen *screen;
struct IntuiMessage *message;
struct NewScreen ns = {
0L,0L,320L,400L,6L,
0,1,HAM|LACE,
CUSTOMSCREEN,NULL,
(UBYTE *)"Display screen",
NULL,NULL };
struct NewWindow nw = {
0L,0L,320L,400L,0L,1L,
MOUSEBUTTONS|CLOSEWINDOW,
ACTIVATE|WINDOWCLOSE|BORDERLESS,
NULL,NULL,
(UBYTE *)"Display window",
NULL,NULL,
0L,0L,320L,400L,CUSTOMSCREEN };
FILE *fp = NULL;
unsigned char line[128];
int maxx,maxy,maxc;
int colors[16];
int cpix,cr,cg,cb,count,pos;
main(argc,argv)
int argc;
char *argv[];
{
unsigned long class;
unsigned short code;
int i,x,y,val,bflg;
GfxBase = (struct GfxBase *)OpenLibrary("graphics.library",0L);
if (GfxBase == NULL) exit(100);
IntuitionBase =
(struct IntuitionBase *)OpenLibrary("intuition.library",0L);
if (IntuitionBase == NULL) {
CloseLibrary(GfxBase);
exit(200);
}
screen = (struct Screen *)OpenScreen(&ns);
if (screen == NULL) {
CloseLibrary(IntuitionBase);
CloseLibrary(GfxBase);
exit(300);
}
nw.Screen = screen;
w = (struct Window *)OpenWindow(&nw);
if (w == NULL) {
CloseScreen(screen);
CloseLibrary(IntuitionBase);
CloseLibrary(GfxBase);
exit(400);
}
vp = &screen->ViewPort;
rp = w->RPort;
/* get the file to read */
if (argc < 2) fp = stdin;
else fp = fopen(argv[1],"r");
if (fp == NULL) error("Can't open input file");
if (fgets(line,128,fp) == NULL) error("Can't read first line");
if (sscanf(line,"%d %d %d\n",&maxx,&maxy,&maxc) != 3) error("Bad header");
if (maxc != 256) error("expecting 256 colors");
for (i = 0; i < 16; i++) {
if (fgets(line,128,fp) == NULL) error("Can't read colors");
if (i == 0 &&
sscanf(line,"%x %x %x %x %x %x %x %x %x %x %x %x %x %x %x %x\n",
&colors[0],&colors[1],&colors[2],&colors[3],&colors[4],&colors[5],
&colors[6],&colors[7],&colors[8],&colors[9],&colors[10],&colors[11],
&colors[12],&colors[13],&colors[14],&colors[15]) != 16)
error("Didn't find 16 colors as expected");
}
/* now set the color map */
for (i = 0; i < 16; i++) {
SetRGB4(vp, (long)i, (long)((colors[i] >> 8) & 0xF),
(long)((colors[i] >> 4) & 0xF),
(long)((colors[i] ) & 0xF));
}
/* now init the read buffer */
line[0] = '\n';
pos = 0;
count = 0;
cr = 0;
cg = 0;
cb = 0;
cpix = '@';
SetDrMd(rp,JAM1);
/* Read through the file and display the results */
bflg = 0;
for (y = 0; y < maxy; y++) {
/* check if there was an attempt to abort */
while ((message=(struct IntuiMessage *)GetMsg(w->UserPort))!=NULL) {
class = message->Class;
code = message->Code;
ReplyMsg(message);
if (class == CLOSEWINDOW) error(NULL);
}
/* now dump the scan line */
for (x = 0; x < maxx; x++) {
if (getnext() == -1) {
bflg = 1;
break;
}
/*
val = ((cr * 7 + cg * 4 + cb * 2) / 2) + 32;
if (val > 126) val = 126;
if ((y % 10) == 9 && (x % 4) == 3) printf("%c",(char)val);
*/
if (x < 320 && y < 400) {
SetAPen(rp,(long)(cpix & 0x3F));
WritePixel(rp,(long)x,(long)y);
}
}
if (bflg == 1) break;
/*
if ((y % 10) == 9) printf("\n");
*/
}
/* wait here until we get a close window message */
while (1) {
WaitPort(w->UserPort);
while ((message=(struct IntuiMessage *)GetMsg(w->UserPort))!=NULL) {
class = message->Class;
code = message->Code;
ReplyMsg(message);
if (class == CLOSEWINDOW) error(NULL);
}
}
}
error(msg)
char *msg;
{
if (msg) {
puts("ERROR: ");
puts(msg);
puts("\n");
}
CloseWindow(w);
CloseScreen(screen);
CloseLibrary(IntuitionBase);
CloseLibrary(GfxBase);
if (fp != NULL && fp != stdin) fclose(fp);
if (msg) exit(-1);
else exit(0);
}
getnext() {
int scr,crgb;
/* first see if we're in a repeat count */
if (count-- > 0) return(0);
/* now see if we need a new buffer */
CHECK(pos);
/* see if we got a repeat count */
if (line[pos] < '?') {
count = (line[pos] - ' ') * 94;
++pos;
CHECK(pos);
count += line[pos++] - ' ';
CHECK(pos);
}
else
count = 1;
/* now bring the character in */
cpix = line[pos++];
if (cpix == '?') cpix = 127;
if (--count < 0) return(0);
/* now set up all the associated variables */
scr = (cpix >> 4) & 3;
switch (scr) {
case 0: crgb = colors[cpix & 0xF];
cr = (crgb >> 8) & 0xF;
cg = (crgb >> 4) & 0xF;
cb = (crgb ) & 0xF;
break;
case 1: cb = cpix & 0xF;
break;
case 2: cr = cpix & 0xF;
break;
case 3: cg = cpix & 0xF;
break;
}
return(0);
}