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How to judge if a texture contains alpha?

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kiffa:
I'm writing a SceneLoader which has a feature: auto setting Object3D's transparency by it's texture. Codes may like that:


--- Code: ---Texture texture = TextureManager.getInstance().getTexture(name);
object3d.setTexture(name);

if(texture.containsAlpha()){
  object3d.setTransparency(0xff);
}

--- End code ---

But there isn't a method like texture.containsAlpha().

LowPolyMan:

--- Quote from: kiffa on March 22, 2013, 12:40:29 pm ---I'm writing a SceneLoader which has a feature: auto setting Object3D's transparency by it's texture. Codes may like that:


--- Code: ---Texture texture = TextureManager.getInstance().getTexture(name);
object3d.setTexture(name);

if(texture.containsAlpha()){
  object3d.setTransparency(0xff);
}

--- End code ---

But there isn't a method like texture.containsAlpha().

--- End quote ---

Mabe load/convert as a bitmap, get the pixels as array, check all first byte value's of 4 (ARGB) ?

EgonOlsen:
You can get a Texture's pixels from an ITextureEffect as well.

kiffa:
Both of the above are not easy to use(for my case). Could you add the method Texture.containsAlpha() ?

LowPolyMan:

--- Quote from: kiffa on March 27, 2013, 04:03:03 am ---Both of the above are not easy to use(for my case). Could you add the method Texture.containsAlpha() ?

--- End quote ---

A Bitmap object in Java/Android has a 'hasAlpha()' flag. So you could load your texture as bitmap and then add it as texture.

Something like the following would do the trick:


--- Code: ---Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.YOURBITMAP);
if (bmp.hasAlpha()==true)
{
  //This bitmap has alpha ..
}
//Now you can pass your bitmap as texture
Texture YOURTEXTURE = new Texture(bmp);

--- End code ---

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