Rendering Target Node - Rendering to texture made simpler.

[krzysztofzablocki]

Problem

CCRenderTexture is abused by many people, people get confused how to render properly into it, like overriding visit methods, mostly because not all cocos nodes are easy to use with CCRenderTexture:

• CCSpriteBatchNode cannot be visited if it's not inside scene tree, if you add it to scene tree and then call [batch visit] between begin and end of RenderTexture rendering you are rendering twice. That's just wrong. You could 'fix' it by hiding the batch at start and then make it visible just before visiting it inside your renderTexture redraw. I still believe that's far from nice solution.
• Animations are _paused if nodes are not in scene node, again could be 'fixed' as in previous point.

'fixed' - means workaround and in my book is really poor.

Solution

Added CCRenderTargetNode - a node that simplifies rendering into CCRenderTexture.

• Whatever you add into it, will be rendered into CCRenderTexture and only there.
• Animations will work since nodes will be in scene tree, batches will work as well. No hacking required and only 1 rendering.
• CCRenderTexture has lazy created .renderTargetNode property that can be used for adding renderTexture content nodes into it, they will be rendered into RenderTexture and only there.
• ( Also it could be used to render into CCRenderTexture that's not in scene tree ( if you'd need that kind of functionality ), you can plainly create it with RenderTexture but you need to retain RenderTexture by yourself so that it doesn't get released before this node. )

[Panajev]

It looks really interesting. It does remove a few roadblocks to CCRenderTexture.

[ricardoquesada]

I like. Scheduled for v2.1

[ricardoquesada]

I sort of merged it it.
What I did was to add the CCTargetRenderNode behavior in CCRenderTexture.
For some reason, it is not working properly now... working on the fix.

[krzysztofzablocki]

It probably doesn't work because you should call visit on the children ( in renderTexture visit method ) when auto-draw mode is turned off.

I designed it this way ( as separate target node ) because it allows you to have more control over it, yet it's still very simple to use.

• You could draw to offscreen render texture and make effects on it very easily.
• You could add an overlay on top of processed texture content (as a child of render texture) and have it drawn standard way, yet still have some fancy effects in renderTexture content.
  etc.

[ricardoquesada]

Thanks.
Yes, I am calling visit on the children. The bug is that for some reason the transformations applied to RenderTexture are not inherited by its children... I found an ugly workaround, but I am trying to figure out the cause of the bug...

CCRenderTargetNode is easy to use, and I like it. What I don't like is to have 3 different nodes with similar features:

• CCGrabber:
• CCRenderTexture
• CCRenderTargetNode

Which one should you use and when ? It is not clear for the user. I think it is confusing. That's why I merged CCRenderTexture and CCRenderTargetNode.

[Panajev]

Would the other patch related to viewport and model view transforms in begin and end do any good to the bug you see now @riq?

[web [iPhone msg]]

On 09/ott/2012, at 17:48, Ricardo Quesada [email protected] wrote:

Thanks.
Yes, I am calling visit on the children. The bug is that for some reason the transformations applied to RenderTexture are not inherited by its children... I found an ugly workaround, but I am trying to figure out the cause of the bug...

CCRenderTargetNode is easy to use, and I like it. What I don't like is to have 3 different nodes with similar features:

CCGrabber:
CCRenderTexture
CCRenderTargetNode
Which one should you use and when ? It is not clear for the user. I think it is confusing. That's why I merged CCRenderTexture and CCRenderTargetNode.

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Reply to this email directly or view it on GitHub.

[krzysztofzablocki]

@ricardoquesada there is still a mistake because currently code in repository is calling [children visit] in draw method but ONLY if you have autodraw enabled. You still need to visit children if you don't have autodraw enabled ( default ) or you break backward compatibility

[ricardoquesada]

@Panajev: Mmm... yes, perhaps.

@krzysztofzablocki: Thanks. What I am doing instead is calling [sprite visit], which works in 99% percent of the cases. But as you mentioned, CCRenderTexture could have other children as well

[Panajev]

@ricardoquesada it might not solve the issue, that I do not know for sure,
but I think it should at least provide an even cleaner foundation to
explore the issue you are experiencing.

On Tue, Oct 9, 2012 at 8:06 PM, Ricardo Quesada [email protected]:

@Panajev https://github.com/Panajev: Mmm... yes, perhaps.

@krzysztofzablocki https://github.com/krzysztofzablocki: Thanks. What I
am doing instead is calling [sprite visit], which works in 99% percent of
the cases. But as you mentioned, CCRenderTexture could have other
children as well

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Reply to this email directly or view it on GitHubhttps://github.com//pull/231#issuecomment-9272588.