Sharp edged sprites

问题

Im new to cocos2D and I would like to draw as

I tried using CCSprite and also tired to resolve it using

[brush setBlendFunc:(ccBlendFunc){GL_ONE, GL_ONE_MINUS_SRC_ALPHA}]; [brush.texture setAliasTexParameters];

But I got only image as

in which the edges are blunt/blur. How I can make the blur edged images as sharp as the first one? Can someone suggest me the right way??

The code I use to generate the above image is

  brush = [CCSprite spriteWithFile:@"sketch.png"];
  [brush setColor:ccc3(0, 0, 0)];
  brush.scale = 1.5f;
  [brush setBlendFunc:(ccBlendFunc){GL_ONE, GL_ONE_MINUS_SRC_ALPHA}];
  [brush.texture setAliasTexParameters];

In gesture method,

  [brush setPosition:curntPoint];
  [brush setRotation:rand() % 360];
  [brush setOpacity:brushAlpha];

Thanks in advance.

来源：https://stackoverflow.com/questions/10949104/sharp-edged-sprites