BaCon BBC

[Deleted]

I updated the libbbc5 library with Charles Pegge's (OxygenBasic author) BBC_SHIFT (right/left bit | math right) and BBC_ROTATE which C doesn't do by default with an operator. I also changed BBC_WAITKEY so it no longer forces an exit of the SDL window and returns to the user program.

I used Charles's BBC_SHIFT to replace the C << left shift operator for testing.


t = BBC_SHIFT(BBC_RND(4) - 1, 6, 0);


vovchik - Can you put your mouse handling routes in a callable function so I can access X/Y position and which mouse button was pressed. Remember that BaCon (with the power of C) isn't always the client calling and it may be an interpreter. Passing back multiple arguments is the trick we need you to perform.

This works for me - but I am not certain of the colour depth.

I think you're right. Look at my ScriptBasic vs. C BASIC example.

Another issue is BBC_PRINTF isn't working. It's not recognizing the variadic parameters. I thought I didn't have MAXSTRING declared in the header but that wasn't it.

[Deleted]

The solution is using the correct BBC_MODE value. Mode 31 is 16 color. (default assignment for BBC_OPEN)  ScriptBasic clocked in at 4.1 seconds so it's good to know SB still has some peddle left.





// C BASIC Polygon

#include <stdio.h>
#include <math.h>
#include <SDL.h>
#include "libbbc5.h"
#include "cbasic.h"

#define PI 3.14159265358979323846

MAIN
BEGIN_FUNCTION
 DIM AS float64 angle, radius, x[10], y[10];
 DIM AS int32 c, t, d, side, sides, xorigin, yorigin, i, l;
 DIM AS Uint32 t1, t2, t3;
 DIM AS char strbuff[15];
 BBC_OPEN();
 BBC_MODE(32);
 t1 = SDL_GetTicks();
 SDL_WM_SetCaption("C BASIC BBC5 - polygon", 0);
 BBC_VDU(26);
 DEF_FOR (i = 1 TO i <= 1000 STEP INCR i)
 BEGIN_FOR
   xorigin = BBC_RND(1250);
   yorigin = BBC_RND(840);
   radius = BBC_RND(300) + 50;
   BBC_ORIGIN(xorigin, yorigin);
   sides = BBC_RND(8) + 2;
   BBC_MOVE(radius, 0);
   BBC_MOVE(10, 10);
   c = BBC_RND(64) - 1;
   t = BBC_SHIFT(BBC_RND(4) - 1, 6, 0);
   BBC_GCOL(0, c, t);
   DEF_FOR (side = 1 TO side <= sides STEP INCR side)
   BEGIN_FOR
     angle = (side -1) * 2 * PI / sides;
     x[side] = radius * cos(angle);
     y[side] = radius * sin(angle);
     BBC_MOVE(0, 0);
     BBC_PLOT(85, x[side], y[side]);
   NEXT
   BBC_MOVE(0, 0);
   BBC_PLOT(85, radius, 0);
   DO
     d = BBC_RND(64) - 1;
   WHILE ((d & 63) != (c & 6));
   BBC_GCOL(0, d, t);
   DEF_FOR (side = 1 TO side <= sides STEP INCR side)
   BEGIN_FOR
     DEF_FOR (l = side TO l <= sides STEP INCR l)
     BEGIN_FOR
       BBC_MOVE(x[side], y[side]);
       BBC_DRAW(x[l], y[l]);
     NEXT
   NEXT
 NEXT
 t2 = SDL_GetTicks();
 t3 = (t2 - t1) / 1000;
 sprintf(strbuff, "%d.4 Seconds.", t3);
 BBC_OFF();
 BBC_VDUSTR(strbuff, 0);
 BBC_WAITKEY();
 BBC_CLOSE();
 RETURN_FUNCTION(0);
END_FUNCTION


[vovchik]

Dear John,

I added a mouse event function so that you can exit before the drawing ends by moving towards the bottom right or pressing the right mouse button....but do not yet flush the event buffer before polling. Anybody know how?

With kind regards,
vovchik


' Polygon demo using BBC basic (brandy) lib with SDL calls
' added some mouse detection

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

PRAGMA INCLUDE SDL.h
PRAGMA OPTIONS -I/usr/include/SDL -D_GNU_SOURCE=1 -D_REENTRANT -DHAVE_OPENGL
PRAGMA LDFLAGS SDL bbc5

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


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

PROTO SDL_GL_SetAttribute ALIAS SDL_ATTRIBUTE
PROTO BBC_VDU
PROTO BBC_MODESTR
PROTO BBC_GCOL
PROTO BBC_PLOT
PROTO BBC_MOVE
PROTO BBC_DRAW
PROTO BBC_ORIGIN
PROTO BBC_OPEN
PROTO BBC_CLOSE
PROTO SDL_WM_SetCaption ALIAS SDL_WINTITLE
PROTO BBC_WAITKEY
PROTO BBC_GETKEY
PROTO BBC_RND
PROTO BBC_SHIFT
PROTO BBC_ROTATE
PROTO echo_on
PROTO echo_off
PROTO printf ALIAS PRINTF
PROTO SDL_PollEvent BBC_EVENT

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


' ***********************
' INITIALIZATION
' ***********************


' define var types
DECLARE angle, radius TYPE double
DECLARE xorigin, yorigin, i, l TYPE int
DECLARE c, t, d, side, sides TYPE int
DECLARE x[10] TYPE double
DECLARE y[10] TYPE double

' ***********************
' INITIALIZATION
' ***********************


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

' ------------------
FUNCTION BBC_MOUSE(int choice)
' ------------------
LOCAL event TYPE SDL_Event
SLEEP 5
event.button.button = -1
SDL_PollEvent(&event)
SELECT choice
CASE 0
IF event.type == SDL_MOUSEMOTION THEN
PRINTF("Current mouse position is : %d \n", event.motion.x)
RETURN event.motion.x
END IF
CASE 1
IF event.type == SDL_MOUSEMOTION THEN
PRINTF("Current mouse position is : %d \n", event.motion.y)
RETURN event.motion.y
END IF
CASE 2
IF event.button.button == SDL_BUTTON_LEFT THEN
PRINT "LEFT BUTTON"
RETURN 1
ELIF event.button.button == SDL_BUTTON_MIDDLE THEN
PRINT "MIDDLE BUTTON"
RETURN 2
ELIF event.button.button == SDL_BUTTON_RIGHT THEN
PRINT "RIGHT BUTTON"
RETURN 3
END IF
END SELECT
RETURN -1
END FUNCTION

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

' ------------------
SUB DRAW()
' ------------------
' draw polygons
LOCAL mymouse TYPE int
FOR i = 1 TO 1000
xorigin = BBC_RND(1250)
yorigin = BBC_RND(840)
radius = BBC_RND(300) + 50
BBC_ORIGIN(xorigin, yorigin)
sides = BBC_RND(8) + 2
BBC_MOVE(radius, 0)
BBC_MOVE(10, 10)
c = BBC_RND(64) + 1
t = BBC_SHIFT(BBC_RND(4) - 1, 6, 0)
BBC_GCOL(0, c, t)
FOR side = 1 TO sides
angle = (double)(((side - 1) * 2) * (PI / sides))
x[side] = (double)(radius * COS(angle))
y[side] = (double)(radius * SIN(angle))
BBC_MOVE(0, 0)
BBC_PLOT(85, (int)x[side], (int)y[side])
NEXT side
BBC_MOVE(0, 0)
BBC_PLOT(85, (int)radius, 0)
REPEAT
d = BBC_RND(64) - 1
UNTIL (d & 63) <> (c & 6)
BBC_GCOL(0, d, t)
FOR side = 1 TO sides
FOR l = side TO sides
BBC_MOVE((int)x[side], (int)y[side])
BBC_DRAW((int)x[l], (int)y[l])
NEXT l
NEXT side
IF BBC_MOUSE(2) = 3 THEN
PRINT "Right button clicked - program exit"
BBC_CLOSE()
END
END IF
IF BBC_MOUSE(0) > 400 AND BBC_MOUSE(1) > 400 THEN
PRINT "Hotspot entered - program exit"
BBC_CLOSE()
END
END IF
NEXT i
END SUB

' ------------------
SUB MK_GUI()
' ------------------
' create SDL window
BBC_OPEN()
BBC_MODESTR(800, 600, 256, 0, 1, 1, -1)
SDL_WM_SetCaption("C BASIC BBC5 - polygon", 0)
BBC_VDU(26)
ANTIALIAS()
' draw polygons
DRAW()
END SUB

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


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

' draw polygons
MK_GUI()
BBC_WAITKEY()
BBC_CLOSE()


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


[Deleted]

Joe,

Would you have any time to help with the documentation effort with the libbbc5 BBC BASIC V graphics library? We need something folks can refer to if they have a BBC BASIC program that they would like to use BaCon or or any other language to run it. I got a start on it HERE but it's only an introduction of sorts. Please let me know soon as this is something that needs to get rolling if this interface is going to be of use to anyone.

John

[Deleted]

I compiled the latest libbbc5.c on XP and then compiled the C BASIC version of the BBC polygon example.

[Deleted]

Here is the Android C BASIC version of the BBC5 polygon example. The BaCon version should compile on Android as well.

[Deleted]

vovchik,

I haven't heard anything from Alex or Joe about an easy to use sprite library for the BBC5 library so I'm going to assume they aren't interested in the BBC5 library. I'm going with my original plan and use Gordon's RTB sprite code for now. Once the sprites are added I'll put on my documentation hat and try to get something put together.

I'm still counting on you for a mouse function. It would be nice to have an event function that could handle both mouse and keyboard events. My SB (non-unicode) keyboard handler returns the key name as a string. It is prefixed with a + (key down) or a - (key up) followed by the key name. (ESC = 'escape') This makes it easy to write a keyboard handler in the host setting the state of modifier keys (shift / ctrl / alt) while process keystrokes. I'm not sure if something like this could also handle mouse events.

John

[bigbass]

Hey John

I think that BBC code has a place here on BaCon
we may also have some long time users of BBC come on board
needing some middle ground to feel comfortable on
and there is probably a lot of good code that could be ported

all of the working examples you guys posted here will get posted on the wiki
as demo code

Joe

[Deleted]

Thanks Joe!

I agree that there are still plenty of casual weekend programmers out there that are looking for something like a QB / traditional BASIC to write utilities and games but on Linux. Your SDL efforts are cross platform which gives your project extra mileage.

If you see anything missing in the BBC5 library a BBC BASIC programmer would expect to be there, please let me know.

[Deleted]

I added BBC_MOUSE based on vovchik's routine.


#include <stdio.h>
#include <math.h>
#include <SDL.h>
#include "libbbc5.h"
#include "cbasic.h"

MAIN
BEGIN_FUNCTION
 DIM AS int m, i;
 BBC_OPEN();
 DEF_FOR (i = 1 TO i <= 3 STEP INCR i)
 BEGIN_FOR
   m = BBC_MOUSE(2);
   PRINT ("Button: = %i\n", m);
   m = BBC_MOUSE(0);
   PRINT ("X: = %i\n", m);
   m = BBC_MOUSE(1);
   PRINT ("Y: = %i\n", m);
 NEXT
 BBC_WAITKEY();
 BBC_CLOSE();
 RETURN_FUNCTION(0);
END_FUNCTION


jrs@laptop:~/libbbc$ ./mouse
Button: = 1
X: = 426
Y: = 8
Button: = 2
X: = 461
Y: = 164
Button: = 3
X: = 173
Y: = 362
jrs@laptop:~/libbbc$

Update

I'm in the process of adding a bit more functionality to the BBC_MOUSE and BBC_GETKEY functions. If a value of 4 is passed to the BBC_MOUSE function it waits for a mouse button to be pressed before returning to the caller. If a 3 is passed, it only a checks for a mouse button press and returns. The BBC_GETKEY will accept a 0 to check for a key and 1 will wait within SDL for a key to be pressed before returning. This gives the programmer the best of both worlds. Keep in mind the longer you let SDL perk without draining the event que, the more unstable it becomes. If you use a BBC_WAITKEY for example, SDL handles the que. I hope to have the new code posted soon.

[Deleted]

I think I have the BBC_MOUSE and BBC_GETKEY working in polling or wait mode for events.

BBC_MOUSE(0) - Waits for mouse movement and returns X position.
BBC_MOUSE(1) - Waits for mouse movement and returns Y position.
BBC_MOUSE(2) - Checks for a mouse button press event and returns.
BBC_MOUSE(3) - Waits for a mouse button to be pressed then returns.

BBC_GETKEY(0) - Polls for a key press event and returns.
BBC_GETKEY(1) - Waits for a key to be pressed then returns.


This really needs some testing and a good example program.

[Deleted]

I noticed that SDL doesn't return anything for function keys and other keys when using the UNICODE option. I'm going to add my keyboard handler from the SB SDL extension module that returns key names with up/down status. (returned as a string value) You can check out the thread on All BASIC if your interested. I will add a BBC_KEYNAME function tomorrow that will provide this functionality. It will follow the same rules as BBC_GETKEY.

[Deleted]

Anyone have a good example of a C function in a shared object (.so) creating and returning a string (pointer) back to the caller? I don't want to make the caller be responsible for freeing it if all possible.

[Deleted]

I tried creating a static global string buffer in the shared object and pass the pointer to the call. It almost works as I'm seeing the pointer to the string returned but not the data.

Here is what the BBC_KEYNAME function looks like.


FUNCTION char *BBC_KEYNAME(int choice)
BEGIN_FUNCTION
 DIM AS int done, e;
 DIM AS SDL_Event event;
 done = 0;
 e = 1;
 DEF_WHILE (NOT done)
 BEGIN_WHILE
   DEF_WHILE (e)
   BEGIN_WHILE
     IF (choice EQ 0) THEN
      e = SDL_PollEvent(AT event);
      SDL_Delay(20);
     ELSE
       e = SDL_WaitEvent(AT event);
     END_IF
     SELECT_CASE (event.type)
     BEGIN_SELECT
       CASE SDL_KEYDOWN:
         strcpy (bbcbuf,"+");
         strcat (bbcbuf,SDL_GetKeyName(event.key.keysym.sym));
         RETURN_FUNCTION(bbcbuf);
         done = 1;
         END_CASE
       CASE SDL_KEYUP:
         strcpy (bbcbuf,"-");
         strcat (bbcbuf,SDL_GetKeyName(event.key.keysym.sym));
         RETURN_FUNCTION(bbcbuf);
         done = 1;
         END_CASE
       CASE SDL_QUIT:
         done = 1;
         SDL_Quit();
         END_CASE
       CASE_ELSE
         RETURN_FUNCTION(0);
         END_CASE
     END_SELECT
   WEND
 WEND
 RETURN_FUNCTION(0);
END_FUNCTION


This is the test program.


#include <stdio.h>
#include <SDL.h>
#include "libbbc5.h"
#include "cbasic.h"

MAIN
BEGIN_FUNCTION
 DIM AS int m, i;
 DIM AS char *s;

 BBC_OPEN();
m = 1;
DO
 s = BBC_KEYNAME(1);
 PRINT ("%s\n", &s);
WHILE (m EQ 1);
 BBC_CLOSE();
 RETURN_FUNCTION(0);
END_FUNCTION  


[vovchik]

Dear John,

Try this in BaCon. It works for me...

With kind regards,
vovchik


' get key function

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

PRAGMA INCLUDE SDL.h
PRAGMA OPTIONS -I/usr/include/SDL -D_GNU_SOURCE=1 -D_REENTRANT -DHAVE_OPENGL
PRAGMA LDFLAGS SDL bbc5

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


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

PROTO BBC_OPEN
PROTO BBC_CLOSE
PROTO SDL_PollEvent BBC_EVENT
PROTO SDL_Delay

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


' ***********************
' INITIALIZATION
' ***********************

DECLARE m TYPE int
DECLARE s$ TYPE STRING

' ***********************
' END INITIALIZATION
' ***********************


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

FUNCTION BBC_KEYNAME$(int choice)
LOCAL done, e TYPE int
LOCAL event TYPE SDL_Event
LOCAL bbc_buffer$ TYPE STRING
done = 0
e = 1
bbc_buffer$ = ""
WHILE NOT(done) DO
WHILE (e) DO
IF choice = 0 THEN
e = SDL_PollEvent(&event)
SDL_Delay(20)
ELSE
e = SDL_WaitEvent(&event)
END IF
SELECT event.type
CASE SDL_KEYDOWN
bbc_buffer$ = "+" & SDL_GetKeyName(event.key.keysym.sym)
RETURN bbc_buffer$
done = 1
CASE SDL_KEYUP
bbc_buffer$ = "-" & SDL_GetKeyName(event.key.keysym.sym)
RETURN bbc_buffer$
done = 1
CASE SDL_QUIT
done = 1
m = FALSE
RETURN "Let's get out of here..."
DEFAULT
bbc_buffer$ = ""
END SELECT
WEND
WEND
RETURN bbc_buffer$
END FUNCTION

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


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

BBC_OPEN()
m = TRUE
WHILE m DO
s$ = BBC_KEYNAME$(1)
PRINT s$
WEND
BBC_CLOSE()
END

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


PS. Nice function. I like it.