B4J Question What would be the most efficient way to create a Sprite Animator?

[wonder]

Since there are no Game libraries (to my knowledge) available to B4J, what would be an efficient way to create a Sprite Animator?

 

[Erel]

Canvas is the only control that supports drawing. Drawings are hardware accelerated so the performance should be quite good.

Check the attached example:

 

[wonder]

Canvas is the only control that supports drawing. Drawings are hardware accelerated so the performance should be quite good.

Check the attached example:

Thank you Erel! I've looked into your example and indeed the performance is great.
However, what if I have a sprite sheet image file, how can I display only specific parts of that image, like you've shown us in your B4A GameView tutorial?

Perhaps, something like this?

Sub Process_Globals
    Dim FrameSizeX   = 100   As Int 'in pixels
    Dim FrameSizeY   = 100   As Int 'in pixels
    Dim MaxNumFrames = 5     As Int
    Dim ActiveFrame  = 0     As Int
    Dim OutputSizeX  = 10%x  As Double
    Dim OutputSizeY  = ...
    ...
End Sub

Sub Timer1_Tick
    'Sprite Animator
    Dim InputX = ActiveFrame * FrameSizeX As Int
    Dim InputY = 0 As Int
    Dim Frame As ????? '<--- is this possible in B4J???
    Frame.SetSource(InputX, InputY, FrameSizeX, FrameSizeY)
    Frame.Draw(OutputX, OutputY, OutputSizeX, OutputSizeY)
    ActiveFrame = ActiveFrame + 1
    If ActiveFrame > MaxNumFrames Then ActiveFrame = 0
End Sub

EDIT: Ok, I think I got it. What I'm looking for is the .DrawImage2 method, right?

Also, how to flip the image? I see a .DrawImageRotated method, but not a "DrawImageFlipped" one...

 

[Erel]

You can do something similar. You should use Canvas.DrawImage2 to draw the correct rectangle from the large image.

 

[wonder]

Thank you! How about horizontal and vertical flipping?

 

[sorex]

if there is no direct way...

store them mirrored in the spritesheet and use an offset value based on the direction.

 

[Jaames]

look at the @Jim Brown's Sprite (from great GameSprite lib) , it should not be too complicated to make such a class for B4J.

 

[Erel]

GameView ported to B4J: https://www.b4x.com/android/forum/threads/gameview-simple-sprites-engine.57950/