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486

answers:

1

I just have a simple sprite - how can I get it to rotate?

A good answer would show how to rotate both a dynamic sprite and a static_mass sprite

A: 

If the sprite is dynamic / non-static, just do like so:

 cpBodySetAngVel(ObjSmSprite.shape->body,0.25); 

For a static body, you can do something like this:

[ObjSmStaticSprite.shape runAction:[CCRepeatForever actionWithAction:
                         [CCSequence actions:
                          [CCRotateTo actionWithDuration:2 angle:180],
                          [CCRotateTo actionWithDuration:2 angle:360],
                          nil]

                         ]];


smgr.rehashStaticEveryStep = YES; //Setting this would make the smgr recalculate all static shapes positions every step

To Summarize, here is a spinning static sprite, following be spinning dynamic sprite.

  // Add Backboard
    cpShape *shapeRect = [smgr addRectAt:cpvWinCenter mass:STATIC_MASS width:200 height:10 rotation:0.0f ];// We're upgrading this 
  cpCCSprite * cccrsRect = [cpCCSprite spriteWithShape:shapeRect file:@"rect_200x10.png"];
    [self addChild:cccrsRect];

  // Make static object update moves in chipmunk
  // Since Backboard is static, and since we're going to move it, it needs to know about spacemanager so its position gets updated inside chipmunk.
  // Setting this would make the smgr recalculate all static shapes positions every step
//  cccrsRect.integrationDt = smgr.constantDt;
//  cccrsRect.spaceManager = smgr;
  // Alternative method: smgr.rehashStaticEveryStep = YES;
  smgr.rehashStaticEveryStep = YES;

  // Spin the backboard
  [cccrsRect runAction:[CCRepeatForever actionWithAction:
                         [CCSequence actions:
                          [CCRotateTo actionWithDuration:2 angle:180],
                          [CCRotateTo actionWithDuration:2 angle:360],
                          nil]

                         ]];


  // Add the hoop
  cpShape *shapeHoop = [smgr addCircleAt:ccp(winSize.width/2.0f,winSize.height/2.0f - 55.0f) mass:1.0 radius: 50 ];
  cpCCSprite * cccrsHoop = [cpCCSprite spriteWithShape:shapeHoop file:@"hoop_100x100.png"];
    [self addChild:cccrsHoop];
  cpBodySetAngVel(cccrsHoop.shape->body,0.25); 

Disclaimer: I'm trying to answer my own question, and this answer might be missing important subtleties - it just represents what I know, so far.

JJ Rohrer
In the summary above, right above 'smgr.rehashStaticEveryStep = YES;', the commented out alternative ccrsRect.integrationDt = smgr.constantDt; cccrsRect.spaceManager = smgr; doesn't seem to work - why not? For many cases, I'm sure that would be a superior approach to 'smgr.rehashStaticEveryStep'
JJ Rohrer