BaCon BBC

[Deleted]

Sweet!

Notice the artifacts? (random lines) David Burnard fixed Brandy's overflow issue in the RND function and BaCon looks like it has the same issue. I think the bbc_rnd will solve these BBC BASIC RND specific problems. It handles both the float and integer return values based on range.

The KEY_WAIT and ALIAS updates were a nice improvement to the BBC library support.

[vovchik]

Dear John,

Thanks. I see the artefacts, too, so I welcome anything that might get rid of them. Are they only with RANDOM? Or is brandy not getting the right numvar type passed somewhere along the line?

With kind regards,
vovchik

[Deleted]

This is the line that fixed the overflow issue.


push_int(TOINT( (randomfraction()*TOFLOAT(value))+1) );


+1 was added. David also changed the seeding to use the millisecond time value rather than a hard coded value with a twist.

[Deleted]

I'm working on a makeover of the libbbc code base. The goal is to be able to compile the library standalone without needing support from Brandy. I'm doing a C BASIC conversion to make the code more readable to BASIC programmers in an effort to promote enhancing the library by the folks that would have the most interest in doing so. Here is a peek of a few local functions that have already been converted. I plan to change the exported function names (BBC_XXXX) to eliminate the need to ALIAS them. I also plan to add a few of the SB extension module functions to make the libbc interface more like a complete BBC BASIC graphics plug-in. (keyboard, RND, RGB and other functions that make sense)


LOCAL SUB trace_edge(int32 x1, int32 y1, int32 x2, int32 y2)
BEGIN_SUB
 DIM AS int32 dx, dy, xf, yf, a, b, t, i;
 IF (x1 EQ x2 AND y1 EQ y2) THEN_DO EXIT_SUB;
 IF (x2 > x1) THEN
   dx = x2 - x1;
   xf = 1;
 ELSE
   dx = x1 - x2;
   xf = -1;
 END_IF
 IF (y2 > y1) THEN
   dy = y2 - y1;
   yf = 1;
 ELSE
   dy = y1 - y2;
   yf = -1;
 END_IF
 IF (dx > dy) THEN
   a = dy + dy;
   t = a - dx;
   b = t - dx;
   DEF_FOR (i = 0 TO i <= dx STEP INCR i)
   BEGIN_FOR
     IF (x1 < left[y1]) THEN_DO left[y1] = x1;
     IF (x1 > right[y1]) THEN_DO right[y1] = x1;
     x1 += xf;
     IF (t < 0) THEN
       t += a;
     ELSE
       t += b;
       y1 += yf;
     END_IF
   NEXT
 ELSE
   a = dx + dx;
   t = a - dy;
   b = t - dy;
   DEF_FOR (i = 0 TO i <= dy STEP INCR i)
   BEGIN_FOR
     IF (x1 < left[y1]) THEN_DO left[y1] = x1;
     IF (x1 > right[y1]) THEN_DO right[y1] = x1;
     y1 += yf;
     IF (t < 0) THEN
       t += a;
     ELSE
       t += b;
       x1 += xf;
     END_IF
   NEXT
 END_IF
END_SUB

LOCAL SUB draw_h_line(SDL_Surface PTR sr, int32 sw, int32 sh, int32 x1, int32 y, int32 x2, Uint32 col)
BEGIN_SUB
 DIM AS int32 tt, i;
 IF (x1 > x2) THEN
   tt = x1;
   x1 = x2;
   x2 = tt;
 END_IF
 IF ( y >= 0 AND y < sh ) THEN
   IF (x1 < 0) THEN_DO x1 = 0;
   IF (x1 >= sw) THEN_DO x1 = sw-1;
   IF (x2 < 0) THEN_DO x2 = 0;
   IF (x2 >= sw) THEN_DO x2 = sw-1;
   DEF_FOR (i = x1 TO i <= x2 STEP INCR i)
   BEGIN_FOR
     PTR ((Uint32 PTR)sr->pixels + i + y * sw) = col;
   NEXT
 END_IF
END_SUB

LOCAL SUB buff_convex_poly(SDL_Surface PTR sr, int32 sw, int32 sh, int32 n, int32  PTR x, int32 PTR y, Uint32 col)
BEGIN_SUB
 DIM AS int32 i, iy;
 DIM AS int32 low = MAX_YRES, high = 0;
 DEF_FOR (i = 0 TO i < n STEP INCR i)
 BEGIN_FOR
   IF (y[i] > high) THEN_DO high = y[i];
   IF (y[i] < low) THEN_DO low = y[i];
 NEXT
 DEF_FOR (iy = low TO iy <= high STEP INCR iy)
 BEGIN_FOR
   left[iy] = MAX_XRES + 1;
   right[iy] = - 1;
 NEXT
 trace_edge(x[n - 1], y[n - 1], x[0], y[0]);
 DEF_FOR (i = 0 TO i < n - 1 STEP INCR i)
 BEGIN_FOR
   trace_edge(x[i], y[i], x[i + 1], y[i + 1]);
 NEXT
 DEF_FOR (iy = low TO iy <= high STEP INCR iy)
 BEGIN_FOR
   draw_h_line(sr, sw, sh, left[iy], iy, right[iy], col);
 NEXT
END_SUB

LOCAL SUB draw_line(SDL_Surface PTR sr, int32 sw, int32 sh, int32 x1, int32 y1, int32 x2, int32 y2, Uint32 col)
BEGIN_SUB
 DIM AS int d, x, y, ax, ay, sx, sy, dx, dy, tt;
 IF (x1 > x2) THEN
   tt = x1;
   x1 = x2;
   x2 = tt;
   tt = y1;
   y1 = y2;
   y2 = tt;
 END_IF
 dx = x2 - x1;
 ax = ABS(dx) << 1;
 sx = ((dx < 0) ? -1 : 1);
 dy = y2 - y1;
 ay = ABS(dy) << 1;
 sy = ((dy < 0) ? -1 : 1);
 x = x1;
 y = y1;
 IF (ax > ay) THEN
   d = ay - (ax >> 1);
   DEF_WHILE (x != x2)
   BEGIN_WHILE
     IF ((x >= 0) AND (x < sw) AND (y >= 0) AND (y < sh)) THEN_DO PTR ((Uint32 PTR)sr->pixels + x + y * sw) = col;
     IF (d >= 0) THEN
       y += sy;
       d -= ax;
     END_IF
     x += sx;
     d += ay;
   WEND
 ELSE
   d = ax - (ay >> 1);
   DEF_WHILE (y != y2)
   BEGIN_WHILE
     IF ((x >= 0) AND (x < sw) AND (y >= 0) AND (y < sh)) THEN_DO PTR ((Uint32 PTR)sr->pixels + x + y * sw) = col;
     IF (d >= 0) THEN
       x += sx;
       d -= ay;
     END_IF
     y += sy;
     d += ax;
   WEND
 END_IF
 IF ((x >= 0) AND (x < sw) AND (y >= 0) AND (y < sh)) THEN_DO PTR ((Uint32 PTR)sr->pixels + x + y * sw) = col;
END_SUB

LOCAL SUB filled_triangle(SDL_Surface PTR sr, int32 sw, int32 sh, int32 x1, int32 y1, int32 x2, int32 y2, int32 x3, int32 y3, Uint32 col)
BEGIN_SUB
 DIM AS int x[3], y[3];
 x[0]=x1;
 x[1]=x2;
 x[2]=x3;
 y[0]=y1;
 y[1]=y2;
 y[2]=y3;
 buff_convex_poly(sr, sw, sh, 3, x, y, col);
END_SUB

LOCAL SUB draw_ellipse(SDL_Surface PTR sr, int32 sw, int32 sh, int32 x0, int32 y0, int32 a, int32 b, Uint32 c)
BEGIN_SUB
 DIM AS int32 x, y, y1, aa, bb, d, g, h;
 DIM AS Uint32 PTR dest;
 aa = a * a;
 bb = b * b;
 h = (FAST_4_DIV(aa)) - b * aa + bb;
 g = (FAST_4_DIV(9 * aa)) - (FAST_3_MUL(b * aa)) + bb;
 x = 0;
 y = b;
 DEF_WHILE (g < 0)
 BEGIN_WHILE
   IF (((y0 - y) >= 0) AND ((y0 - y) < sh)) THEN
     dest = ((Uint32 PTR)sr->pixels + x0 + (y0 - y) * sw);
     IF (((x0 - x) >= 0) AND ((x0 - x) < sw)) THEN_DO PTR (dest - x) = c;
     IF (((x0 + x) >= 0) AND ((x0 + x) < sw)) THEN_DO PTR (dest + x) = c;
   END_IF
   IF (((y0 + y) >= 0) AND ((y0 + y) < sh)) THEN
     dest = ((Uint32 PTR)sr->pixels + x0 + (y0 + y) * sw);
     IF (((x0 - x) >= 0) AND ((x0 - x) < sw)) THEN_DO PTR (dest - x) = c;
     IF (((x0 + x) >= 0) AND ((x0 + x) < sw)) THEN_DO PTR (dest + x) = c;
   END_IF
   IF (h < 0) THEN
     d = ((FAST_2_MUL(x)) + 3) * bb;
     g += d;
   ELSE
   d = ((FAST_2_MUL(x)) + 3) * bb - FAST_2_MUL((y - 1) * aa);
     g += (d + (FAST_2_MUL(aa)));
     INCR y;
   END_IF
   h += d;
   INCR x;
 WEND
 y1 = y;
 h = (FAST_4_DIV(bb)) - a * bb + aa;
 x = a;
 y = 0;
 DEF_WHILE (y <= y1)
 BEGIN_WHILE
   IF (((y0 - y) >= 0) AND ((y0 - y) < sh)) THEN
     dest = ((Uint32 PTR)sr->pixels + x0 + (y0 - y) * sw);
     IF (((x0 - x) >= 0) AND ((x0 - x) < sw)) THEN_DO PTR (dest - x) = c;
     IF (((x0 + x) >= 0) AND ((x0 + x) < sw)) THEN_DO PTR (dest + x) = c;
   END_IF
   IF (((y0 + y) >= 0) AND ((y0 + y) < sh)) THEN
     dest = ((Uint32 PTR)sr->pixels + x0 + (y0 + y) * sw);
     IF (((x0 - x) >= 0) AND ((x0 - x) < sw)) THEN_DO PTR (dest - x) = c;
     IF (((x0 + x) >= 0) AND ((x0 + x) < sw)) THEN_DO PTR (dest + x) = c;
   END_IF
   IF (h < 0) THEN
     h += ((FAST_2_MUL(y)) + 3) * aa;
   ELSE
     h += (((FAST_2_MUL(y) + 3) * aa) - (FAST_2_MUL(x - 1) * bb));
     INCR x;
   END_IF
   INCR y;
 WEND
END_SUB

LOCAL SUB filled_ellipse(SDL_Surface PTR sr, int32 sw, int32 sh, int32 x0, int32 y0, int32 a, int32 b, Uint32 c)
BEGIN_SUB
 DIM AS int32 x, y, y1, aa, bb, d, g, h;
 aa = a * a;
 bb = b * b;
 h = (FAST_4_DIV(aa)) - b * aa + bb;
 g = (FAST_4_DIV(9 * aa)) - (FAST_3_MUL(b * aa)) + bb;
 x = 0;
 y = b;
 DEF_WHILE (g < 0)
 BEGIN_WHILE
   draw_h_line(sr, sw, sh, x0 - x, y0 + y, x0 + x, c);
   draw_h_line(sr, sw, sh, x0 - x, y0 - y, x0 + x, c);
   IF (h < 0) THEN
     d = ((FAST_2_MUL(x)) + 3) * bb;
     g += d;
   ELSE
     d = ((FAST_2_MUL(x)) + 3) * bb - FAST_2_MUL((y - 1) * aa);
     g += (d + (FAST_2_MUL(aa)));
     INCR y;
   END_IF
   h += d;
   INCR x;
 WEND
 y1 = y;
 h = (FAST_4_DIV(bb)) - a * bb + aa;
 x = a;
 y = 0;
 DEF_WHILE (y <= y1)
 BEGIN_WHILE
   draw_h_line(sr, sw, sh, x0 - x, y0 + y, x0 + x, c);
   draw_h_line(sr, sw, sh, x0 - x, y0 - y, x0 + x, c);
   IF (h < 0) THEN
     h += ((FAST_2_MUL(y)) + 3) * aa;
   ELSE
     h += (((FAST_2_MUL(y) + 3) * aa) - (FAST_2_MUL(x - 1) * bb));
     INCR x;
   END_IF
   INCR y;
 WEND
END_SUB


[vovchik]

Dear John,

Nice idea. Please be aware that the math lib (libm) contains many reserved varnames/macros/functions, and vars such as y1, y2 may not work as expected as a result. I would use longer var varnames just to avoid this issue. I have already been a victim of this. And libm gets linked in automatically by bacon when a function such as COS is called, as I recall, so there is probably no need to have it explicitly in PROTO, although it doesn't hurt.

With kind regards,
vovchik

[bigbass]

Hey guys

how about at least one simple example
and it took just a few minutes

just ignore the word windows when you see it ok we can get around without that
www.bbcbasic.co.uk/bbcwin/manual/bbcwin3.html
bb4w.wikispaces.com/BBC+BASIC+Language
bb4w.wikispaces.com/Tutorials

check the MODEs
Joe




' ALIAS to make coding easy and add system calls

PRAGMA INCLUDE SDL.h
PRAGMA OPTIONS -I/usr/include/SDL
PRAGMA LDFLAGS m SDL bbc

PROTO init_screen       ALIAS SCREEN
PROTO emulate_mode      ALIAS MODE
PROTO emulate_origin    ALIAS ORIGIN
PROTO emulate_off       ALIAS OFF
PROTO emulate_gcol      ALIAS GCOLOR
PROTO emulate_draw      ALIAS DRAW
PROTO emulate_move      ALIAS MOVE
PROTO end_screen        ALIAS ENDSCREEN
PROTO SDL_WM_SetCaption ALIAS TITLE
PROTO system            ALIAS SYS



SCREEN()
TITLE("BaCon BBC system test", 0)
MODE(9)
ORIGIN(200, 100)
OFF()
GCOLOR(0, 10)
x = 0
y = 0

SYS ("ls")
MOVE ( 250,200)
MOVE( 500,300)
DRAW(205,150,350)

INPUT wait$

ENDSCREEN()

[Deleted]

Thanks Joe & vovchik for participating in the BaCon BBC library project. You guys make a great team! Here is screen shot of Joe's last example with a minor change.




' ALIAS to make coding easy and add system calls

PRAGMA INCLUDE SDL.h
PRAGMA OPTIONS -I/usr/include/SDL
PRAGMA LDFLAGS m SDL bbc

PROTO init_screen ALIAS SCREEN
PROTO emulate_mode ALIAS MODE
PROTO emulate_origin ALIAS ORIGIN
PROTO emulate_off ALIAS OFF
PROTO emulate_gcol ALIAS GCOLOR
PROTO emulate_draw ALIAS DRAW
PROTO emulate_move ALIAS MOVE
PROTO emulate_vdustr ALIAS GPRINT
PROTO end_screen ALIAS ENDSCREEN
PROTO SDL_WM_SetCaption ALIAS TITLE

SCREEN()
TITLE("BaCon BBC system test", 0)
MODE(9)
ORIGIN(200, 100)
OFF()
GCOLOR(0, 10)
x = 0
y = 0
GPRINT ("BBC Old School Graphics", 0)
MOVE ( 250,200)
MOVE( 500,300)
DRAW(205,150,350)

INPUT wait$

ENDSCREEN()


[vovchik]

Dear John,

Nice and simple. Reminds me of something I may have once done on my Commodore Pet (32k RAM!), although it ws monochrome.

With kind regards,
vovchik

[Deleted]

Changing screen MODEs is a nice feature. The text display based on MODE is also cool. This project may be the first BBC (like) BASIC C translator.

[konaexpress]

Ummmmmm.....

Just wondering as to what you are trying to do with this idea?

Is it a "wonder if I can do this?" kind of thing?




John

[Deleted]

Just wondering as to what you are trying to do with this idea?

I was hoping that naming the library LIBBBC would make it obvious. I'm trying to make the libbbc library as friendly to use as IUP. I personally don't see any value in the core BBC BASIC as a language but the simplified graphics syntax is appealing.

[alexfish]

Hi John

As regards a BBC compiler there was or used to be a Compiler for BBC or RE BASIC5 I think

Also as regards the Naming LIb/BBC as far as the Linux Community is Concerned there is on offer a BBC module from RT

best read here.
BBC Module . Linux

As regards using the SDL lib Re: the aspect of a lib that used by BRANDY using BaCon with the Simplified SYNTAX is very Appealing

BR
Alex

[Deleted]

I purchased a copy of BBC4W and invited Richard to join the All BASIC Developer forum which he did. I gave BBC4W an objective review. I suggested the best direction for Richard was to capitalize on the RaspBerry PI / dev board craze and provide a RISC based BBC4ARM that carters to hobbyists looking for cheap fun. He could package a board and his BASIC in (E)ROM and it could be the next LEGO of dev board projects. He said I was full of shit in not so many words so I moved on.

As regards using the SDL lib Re: the aspect of a lib that used by BRANDY using BaCon with the Simplified SYNTAX is very Appealing

Just a reminder, this is compilable on Android native (C4droid) with the same UI as a desktop. (no code changes required)

[vovchik]

Dear all,

Here is a little BBC-BaCon flood fill demo:


' FloodFill - RosettaCode BBC BASIC

' ***********************
' COMPILER DIRECTIVES
' ***********************

PRAGMA INCLUDE SDL.h
PRAGMA OPTIONS -I/usr/include/SDL
PRAGMA LDFLAGS m SDL bbc

' ***********************
' END COMPILER DIRECTIVES
' ***********************


' ***********************
' EXTERNAL FUNCTIONS
' ***********************

PROTO init_screen ALIAS SCREEN
PROTO emulate_modefn ALIAS GETMODE
PROTO emulate_mode ALIAS MODE
PROTO emulate_origin ALIAS ORIGIN
PROTO emulate_off ALIAS OFF
PROTO emulate_gcol ALIAS GCOLOR
PROTO emulate_move ALIAS MOVE
PROTO emulate_vdustr ALIAS GPRINT
PROTO end_screen ALIAS ENDSCREEN
PROTO emulate_vdu ALIAS VDU
PROTO emulate_point ALIAS POINT
PROTO emulate_line ALIAS LINE
PROTO emulate_circle ALIAS CIRCLE
PROTO SDL_WM_SetCaption ALIAS TITLE
PROTO SDL_PollEvent ALIAS BBC_GETKEY
PROTO SDL_GL_SetAttribute ALIAS SDL_ATTRIBUTE

' ***********************
' END EXTERNAL FUNCTIONS
' ***********************


' ***********************
' SUBS & FUNCTIONS
' ***********************

' ------------------
SUB FLOOD(int X, int Y, int C)
' ------------------
LOCAL L, R TYPE int
' PRINT POINT(X, Y)
IF POINT(X, Y) <> C THEN
GOTO SKIP
END IF
L = X
R = X
WHILE POINT(L - 2, Y) = C DO
DECR L, 2
WEND
WHILE POINT(R + 2, Y) = C DO
INCR R, 2
WEND
LINE(L, Y, R, Y)
FOR X = L TO R STEP 2
CALL FLOOD(X, Y + 2, C)
CALL FLOOD(X, Y - 2, C)
NEXT
LABEL SKIP
END SUB

' ------------------
SUB KEY_WAIT()
' ------------------
LOCAL event TYPE SDL_Event
WHILE TRUE DO
WHILE BBC_GETKEY(&event) DO
SELECT event.type
CASE SDL_KEYUP
' If return is pressed,  quit
' see http://www.libsdl.org/release/SDL-1.2.15/docs/html/sdlkey.html
IF event.key.keysym.sym = SDLK_RETURN THEN
OFF()
ENDSCREEN()
END 0
END IF
CASE SDL_QUIT
END 0
END SELECT
WEND
WEND
END SUB

' ------------------
SUB ANTIALIAS()
' ------------------
SDL_ATTRIBUTE(SDL_GL_MULTISAMPLEBUFFERS, 1)
SDL_ATTRIBUTE(SDL_GL_MULTISAMPLESAMPLES, 4)
END SUB

' ------------------
SUB MK_DRAWING()
' ------------------
DECLARE FILL TYPE int
FILL = 1
LOCAL x, y TYPE int
LOCAL T1$, T2$, T3$ TYPE STRING
T1$ = "BaCon BBC FLOOD FILL"
T2$ = "BBC Old School Graphics"
T3$ = "Press <RETURN> to quit"
SCREEN()
TITLE(T1$, 0)
ANTIALIAS()
MODE(32)
VDU(5)
PRINT "MODE: ", GETMODE()
GCOLOR(0, 10, 5)
ORIGIN(100, 120)
CIRCLE(640, 512, 500, 1)
GCOLOR(0, 3, 10)
CIRCLE(500, 600, 200, 1)
GCOLOR(0, 5, 6)
FLOOD(600, 200, 15)
ORIGIN(0, 0)
MOVE(580, 100)
GCOLOR(0, 2, 3)
GPRINT(T2$, LEN(T2$))
GCOLOR(0, 2, 4)
MOVE(585, 70)
GPRINT(T3$, LEN(T3$))
END SUB

' ***********************
' END SUBS & FUNCTIONS
' ***********************


' ***********************
' MAIN
' ***********************

MK_DRAWING()
KEY_WAIT()

' ***********************
' END MAIN
' ***********************


With kind regards,
vovchik

[bigbass]

Hey vovchik

a very nice job with many things there !

you get a 100% on the rosetta challenge
but you get many extra credit points for

1.)not using bbc but simulating it on bacon and having to invent some more alias

2.) for adding event handing (and before I had a chance to give it a try )

3.) for creating a FLOOD routine

4.) just getting it ported from another language

Joe