simplest way to display an animated png file?

[CCJ]

Hi all,

I am having some trouble creating what should be a simple animation for an iPhone app I'm working on--

Code (glbasic) Select Expand


LOADANIM "yesnobuttons.png", 0, 295,300
FOR y=0 TO 19
  DRAWANIM 0, y, 0, 100
  SHOWSCREEN
  MOUSEWAIT
NEXT

MOUSEWAIT


The animation is supposed to draw two buttons rising up out of the ground for the user to press, but instead I just get crazy mangled looking results.  Is there an easy way to just load in and display a pre-made animation, and have it run through its frames in one location (i.e. not require any user input to etc. to change frames as in a walking animation).  Also, what's the best way to control the speed at which an animation iterates through its frames?  As you can see here I just made it pause at every frame so I could check on what was being displayed, but in the final app the animation should run smoothly on its own when called.

[Leginus]

i would do something like

Code (glbasic) Select Expand

LOADANIM "yesnobuttons.png", 0, 295,300
ani=0

WHILE KEY(01) = FALSE
   delta=delta+1
   IF delta>6   //Framerate of your choice
      INC ani
      IF ani>19
         ani=0
      ENDIF
   ENDIF
  DRAWANIM 0, ani, 0, 100
  SHOWSCREEN
WEND


[Ian Price]

Leginus, your code won't work properly - as soon as delta is greater than 6 it will run through the entire animation before resetting delta to zero. While delta is less than (or equal to) six there will be no animation and only the last anim frame will be displayed.

What you probably meant is -

Code (glbasic) Select Expand



LOADANIM "yesnobuttons.png", 0, 295,300

anim=0

WHILE TRUE

INC delta

IF delta>6
INC anim
delta=0
ENDIF

IF anim>19 THEN anim=0

DRAWANIM 0,anim,0,100

SHOWSCREEN

WEND


[Leginus]

oops. its late

[Moebius]

The only reason I can think of for why your results might be 'mangled' is if you've got the width and height of each frame wrong.
Creating in image with the frames side by side is the easiest way to load and use an animation - if you've got the height and width parameters right, it should work perfectly, and you can make it 'animate' more slowly by only changing the frame displayed once every few logic updates, as described below.