cocos2d for iPhone

A fast, easy to use, free, and community supported 2D game engine

1. 

   e1234
   Member

   Hi,

   I have added a sprite to a scene, however I have also implement a draw method within the scene to draw a polygon. The draw method uses standard OpenGL to draw the polygon, however the sprite covers the polygon. I would like to know how I can draw the polygon over the sprite.

   Thanks,
   Etienne

   Posted 1 year ago #
2. 

   e1234
   Member

   Think I got it now, will try tomorrow morning. I need a class inheriting from ccnode. In this class I overide the draw method to draw my polygon. Then I add the ccnode to the scene after my sprite. Thus the sprite is drawn first and then the class with ccnode...

   Posted 1 year ago #
3. 

   marco2D
   Member

   it's interesting, please let me to know about your solution if does work, thanks

   Posted 1 year ago #
4. 

   ehoffman
   Member

   The draw method uses z-index 0 of the current node (scene, sprite or whatever). To draw over the node/scene you just need to add the node/scene below z=0, e.g. [self addChild:sprite z:-1];

   Posted 1 year ago #
5. 

   e1234
   Member

   Thanks! Just changed [self addChild:sprite] to [self addChild:sprite z:-1]; thus the sprite are ordered below the polygon!

   Posted 1 year ago #
6. 

   v3nom
   Member

   Hello:

   Can you please share the code to draw the poligon in openGL?

   Thanks!

   Posted 1 year ago #
7. 

   steg90
   Member

   Something like...

   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
   glLoadIdentity();
   glTranslatef(-1.5f,0.0f,-6.0f);
   glBegin(GL_QUADS);
   glVertex3f(-1.0f, 1.0f, 0.0f);
   glVertex3f( 1.0f, 1.0f, 0.0f);
   glVertex3f( 1.0f,-1.0f, 0.0f);
   glVertex3f(-1.0f,-1.0f, 0.0f);
   glEnd();

   Or something along those lines :-)

   Posted 1 year ago #
8. 

   tran_tuan
   Member

   Also note that Cocos2d has some basic draw function available such as ccDrawLine, ccDrawDrawPoly... that can save you loads of effort. Have a look in CCDrawingPrimitives.m

   Posted 11 months ago #

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