Away3D Forum Animated AlphaMask

Found a solution:

You can use ProjectiveTextureMethod to project an alpha texture on a textured mesh. All you need is a MaterialBase with alphaBlending enabled, a BitmapTexture with alpha channel to sample alpha from.

projectedAlphaHole = new BitmapTexture( new BitmapWithTransparency().bitmapData );
texProjector = new TextureProjector( projectedAlphaHole );
projTexMethod = new ProjectiveTextureMethod( texProjector, ProjectiveTextureMethod.ALPHA );
materialToPutAlphaMaskOn.addMethod( projTexMethod ); 

To make this work you need to add a new BlendMode to ProjectiveTextureMethod.as. Search for the follwing lines:

if (_mode == MULTIPLY)
{...}
else if (_mode == ADD)
{...}
else if (_mode == MIX)
{...} 

and add the follwing for an “alpha stencil”:

else if ( _mode == ALPHA )
{
   code += "mov " + targetReg + ".w, " + col + .w     \n";
} 

Finally add a static const on top of class to identify the new BlendMode:


public static const ALPHA : String = "alpha";

Now have fun with


ProjectiveTextureMethod( texProjector, ProjectiveTextureMethod.ALPHA );

Animated AlphaMask Software: Away3D 4.x

Paul Schlichter, Newbie Posted: 04 May 2012 04:22 PM Total Posts: 13 Hi there, Anyone knows how to animate an alpha mask? The idea is to have a moving alpha hole on a plane. Treid AlphaMaskMethod, but i can’t find any way to animate the secondaryUVs… Thanks for your help, best regards
Paul Schlichter, Newbie Posted: 07 May 2012 10:39 AM Total Posts: 13 [ # 1 ] Found a solution: You can use ProjectiveTextureMethod to project an alpha texture on a textured mesh. All you need is a MaterialBase with alphaBlending enabled, a BitmapTexture with alpha channel to sample alpha from. `projectedAlphaHole = new BitmapTexture( new BitmapWithTransparency().bitmapData ); texProjector = new TextureProjector( projectedAlphaHole ); projTexMethod = new ProjectiveTextureMethod( texProjector, ProjectiveTextureMethod.ALPHA ); materialToPutAlphaMaskOn.addMethod( projTexMethod );` To make this work you need to add a new BlendMode to ProjectiveTextureMethod.as. Search for the follwing lines: `if (_mode == MULTIPLY) {...} else if (_mode == ADD) {...} else if (_mode == MIX) {...}` and add the follwing for an “alpha stencil”: `else if ( _mode == ALPHA ) { code += "mov " + targetReg + ".w, " + col + .w \n"; }` Finally add a static const on top of class to identify the new BlendMode: `public static const ALPHA : String = "alpha";` Now have fun with `ProjectiveTextureMethod( texProjector, ProjectiveTextureMethod.ALPHA );`

Animated AlphaMask

Login

Away3D Forum

Member Login