How to kill last image of animation...

[Wizard]

Hi everyone. My game is a SpaceFighter programmed with DelphiX. I followed Mr Farmer's advice and created a seperate class for the explosion, i.e.when my bullet hits my enemy the enemy image is replaced by an animated explosion:

 //The explosion class
  TExplode = class(TImageSprite)
  public
    constructor Create(AParent: TSprite); override;
  end;


Constructor TExplode.Create(AParent: TSprite);
begin
  inherited Create(AParent);
  self.Image := Form1.DXImageList1.Items[form1.ExplodeImageIndex];
  self.X := Enemy.X;
  self.Y := Enemy.Y;
  self.Width := Enemy.Image.Width;
  self.Height := Enemy.Image.Height;
  self.PixelCheck := False;
  self.AnimCount := Image.PatternCount;
  //self.AnimLooped:= True;
  self.AnimSpeed:= (60/1000) * UpdateSpeed;
end;

procedure TForm1.BulletCollision(Sender:TObject;var done:Boolean);
begin
   if (sender is TEnemy) then
        begin
             Enemy := TEnemy(sender);
             if (not Enemy.Hit) then
                begin
                     Explode := TExplode.Create(dxSpriteEngine1.Engine);
                     Enemy.hit := true;
                     Enemy.Dead;
                     Bullet.Dead;
                     Points := Points + 1000;
                     EnemyCount := EnemyCount + 1;
                     Enemy := TEnemy.create(dxspriteEngine1.Engine,dximageList1,EnemyLeftImageIndex);
                end;
        end
         else ...

Problem is that once the bullet hits the enemy the explosion animation runs perfectly but stops at the last image of the animation. This "last" image of the animation then stays on ths screen. How do I kill it? Explode.Dead kills it but then the animation does not run :-(

[DraculaLin]

See this Sprite Engine shooter demo.It use Asphyre but Sprite Engine is the same as DelphiX.
http://www.afterwarp.net/forum/thread220.html

[Wizard]

Thanks, I'll have a look :-)

I tried the following:

procedure TExplode.DoMove(MoveCount : integer);
begin
lifecount := lifecount +1;
if lifecount > 5 then
self.Dead;
end;

It works but the animation is too fast, no matter how slow I set the animspeed * updatespeed

Another solution is that I add a black (trransparent) image at the end of the animation...it works but I don't know if it will cause problems because the image is simply transparent and not realy dead. I tried it for long periods and there doesn't seem to be any negative effects. Maybe someone can comment on the last solution?

Thanks!

[Legolas]

Try this:

[pascal]
procedure TExplode.DoMove(MoveCount : integer);
begin
inherited doMove(MoveCount);
lifecount := lifecount +1;
if lifecount > 5 then
Dead;
end;
[/pascal]

[Wizard]

Legolas, it works but as I said before the animation is just too fast, you only see a little bit more than a flicker

What about if I just set the last image in the animation to be transparent without the doMove and simply calling the explode in the collision procedure?

[FNX]

Try to slow down your Animspeed, then check AnimPos vs Animcount
and you're done

something like this

[pascal]
if (AnimPos > ((AnimCount-1)-AnimSpeed)) then Dead[/pascal]

should work.

Anyway make large use of screen debugs (TextOut) so that you may
understand how the sprite behave

[Wizard]

Tanks guys. FNX can you explain what you mean with large TextOuts? Do you mean that large TextOuts will slow down the game so that sprites move slower?

Maybe my over all speed is too fast because I tried your suggestions and I get the same effects...FPS is 1000 div 200 and the OneMSec is 100/1000 and UpdateSpeed := (NewTime - OldTime) * OneMSec; Maybe DelphiX is not good enough...

I tried getting Animspeed down and even with a Null value I get the same effects.

[FNX]

Hi Wizard,
no i mean "large use" of Textout, as a debug so that you can see how
anim is going, for example print on screen the AnimPos value
and see if it goes from 0 to AnimCount-1 correctly or not Sorry for my
bad english

About speed, this was discussed a lot in the past, I try to remember
everything in hope to help you (corrections are welcome of course!)

-Put a TimeBeginPeriod(1) inside you FormCreate event
-Set the Timer Interval at 1000/60 (that is 16 or somethin')
-Inside the Timer loop set Engine.DoMove(LagCount)
-Inside your sprites classes use, for ex: X = X + Speed*MoveCount

if you're using UnDelphiX to achive more speed be sure your main form
is declared as TDXForm and the DXDraw Options has do3D true.
WaitVBlank is up to you, i always turn it on even if it slow things down.

Last but not least, you don't need to code a custom constructor for your
class but inherit from TImageSprite that is more than enough. I try
to write something but don't take it as gold

[pascal]
type
TMyExplosionSprite = class(TImageSprite)
private
//... whatever you need
public
procedure DoMove(MoveCount: Integer); override;
end;

// when you need to create a new explosion, i think in some DoCollision event of any other sprite do

with TExplosionSprite.Create(Form.DXSpriteEngine.Engine ) do
begin
Image := Form.DXImageList.Items.Find('explosion');
Width := Image.PatternWidth;
Height := Image.PatterHeight;

X := XPos; //whatever...
Y := YPos; //whatever...
Z := ZPos; //whatever but above the other sprites

AnimCount := Image.PatternCount;
AnimSpeed := 0.06; //whatever...
AnimLooped:= True;

Visible := True;
end;

procedure TExplosionSprite.DoMove(MoveCount : Integer);
begin
inherited DoMove(MoveCount);

AnimLooped := True;
AnimSpeed := 0.06*MoveCount; //whatever...

// if AnimPos has reached the last frame
if (AnimPos >= ((AnimCount-1)-AnimSpeed*MoveCount) then Dead;
end;

[/pascal]

That, with the obvious needed corrections (i don't have delphi here so i wrote it by memory ops: ) should work, at least is similar to what i use
for games myself

[Wizard]

Hi FNX, thanks for your comments/help. I have found that setting the timer to a slow rate might cause jerky movement, therefore I've got it a lot faster and I use updatespeed to get time based movement in stead of frame based movement. Also, my dxDraw resolution is 1024/768 16 bit.

I don't have do3d but I'll do some tests, WaitVblank slows things down too much. I downloaded your game about the Japanese robots and I liked your explosions a lot One thing I did notice is that your sprites move a lot slower than mine.

There's a lot of talk that DelphiX is outdated but I think it still has a lot of power Tip,I see you're using Find for the image change, an Index is a lot faster :-)

My game is working very well and it runs at the same speed on slow and fast machines...I'll get the animation right, I just need to do a few more tests :-) One thing I did realize is that there's a lot of different ways to do things when programming :-)

Happy coding :-)

[Wizard]

Ok guys, it's working :-)

Thanks to FNX for this:

[pascal]self.AnimSpeed := 0.06;
if (AnimPos >= ((AnimCount-1)-AnimSpeed)) then
self.Dead;[/pascal]

My AnimSpeed was too high, 0.06 works perfectly!