After a discussion an another thread about filled circles, I made a little program using FILLPOLY_P to simulate a fillled circle. It was really slow because of the use of a FOR loop to make a list of coordinates to feed the FILLPOLY function. One day Han told me it would be more efficient to call MAKELIST for building lists, so I modified it a bit, and this is now REALLY faster

You can push the attached program in your calc or the simulator, run "circles" for a quick demo drawing random circles on screen at a nice speed, or use the EXPORTed FILLCIRCLE_P(centerX, centerY, radius, color) function in your program.

You can also copy/past the function in your program if you want to use it but don't want to rely on an external lib.

NB : these are not perfect circles, they are not suitable for mathematics purposes. Also, very small circle may look weird.

Enjoy

If they just throw away the outputs as they go instead of making a list and throwing it away, then that's nice; we just got speedy effectual mapping.

Very good work

I'm not sure MAKEMAT would support multiple statements. Did you try it ?

I replaced the two FOR loops in render routine in Trailblazer by a MAKEELIST, that's about 3 or 4 FPS earned.

If I got it right, only a Home variable can be used with MAKELIST ?

Han: Confirmed; from Home 'MAKEMAT(PRINT(I); PRINT(J); RETURN 0,25,25)' fails syntax checking with the cursor positioned right before the first ";". Also, I've had problems with 'MAKELIST(MAKELIST(X,X,1,10),X,1,10)' passing the syntax check but presently failing with 'Error: Bad argument type'.

Necrobump:

Thanks to this routine, we can actually do circle-based fade-in/out animations, like in Zelda, in addition to stuff like dark cavern/dungeon effects!




The edited code by MacBernick looks like this:

Code: [Select]

FILLCIRCLE_P(cx, cy, r, color);

EXPORT circles()
BEGIN
DIMGROB_P(G1,320,240);
DIMGROB_P(G2,320,240);
DIMGROB_P(G3,320,240);
BLIT_P(G1,G0);
FOR A FROM 220 DOWNTO 0 DO
      RECT_P(G2,#000000);
      FILLCIRCLE_P(160, 120, A, #FF00FF);
BLIT_P(G3,G1);
BLIT_P(G3,0,0,320,240,G2,0,0,320,240,#FF00FF);
BLIT_P(G3);
END;
END;



EXPORT FILLCIRCLE_P(cx, cy, r, color)
BEGIN
   LOCAL s, cl := {}, angle := HAngle;
   HAngle := 1;

   LOCAL cl :=
      MAKELIST({EVAL(r * COS(S) + cx), EVAL(r * SIN(S) + cy)},
         S, 0, 359, 10);

   HAngle := angle;
   FILLPOLY_P(G2,cl, #FF00FF,255);
END;

You need multiple GROBs or at least a GROB large enough for each frame, because it involves transparency.

Why the EVALs? Also, angle should be a pragma.

Every time I see cool stuff for the prime, it makes me wish my parents let me buy one...

Nice job!

Now I wish I got a HP Prime instead of a V200


It looks like it would be useful for games with circles.