[Qt-interest] QGraphicsItem and Threads

[Brad Howes]

On Oct 19, 2009, at 11:22 AM, Ole Streicher wrote:

> That works for me. Do I still need to use brush.moveToThread()
> somewhere?


I don't think so, because Qt's implicit sharing model is thread-safe,  
though I am not sure about the mechanism by which it accomplishes  
this. I believe, but do not know for a fact, that you will have two  
QBrush objects, one in the creator thread, and one in the asynchronous  
slot thread, with the same values but different thread ownerships.

Based on your code, an even better approach would be to just emit the  
colors and not the QBrush objects, and have the items just update  
their brush to use the new color. You save on object creation /  
destruction.

Brad

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Brad Howes
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