Question

I’m trying to draw a bitmap in flex,the original bitmap is

but, actually it show up in the app looks like

here is the code:

this.component.graphics.beginBitmapFill(leakBitmapData);
this.component.graphics.drawRect(leakPoint.x-halfWidth,leakPoint.y-halfHeight,leakBitmapData.width,leakBitmapData.height);
this.component.graphics.endFill();

only when I draw the rect at (0,0),it looks right.
Why?

Answer 1

If you want to draw something outside the origin, you will need to do a matrix translation on the BitmapData. Something like this:

var px:int = leakPoint.x - halfWidth;
var py:int = leakPoint.y - halfHeight;
var translationMatrix:Matrix = new Matrix;
translationMatrix.tx = px;
translationMatrix.ty = py;

this.component.graphics.beginBitmapFill(leakBitmapData, translationMatrix);
this.component.graphics.drawRect(px, py, leakBitmapData.width, leakBitmapData.height);
this.component.graphics.endFill();