Primitives and sprites Z index in Cocos2D-x 3.0 is not consistent?

问题

I have two layers. Each layer has a primitive drawing in it with OpenGL like this:

void Layer1::drawPolygon()
{
    glLineWidth(1);
    DrawPrimitives::setDrawColor4B(255,255,255,255);
    DrawPrimitives::setPointSize(1);

    // Anti-Aliased
    glEnable(GL_LINE_SMOOTH);

    // filled poly
    glLineWidth(1);
    Point filledVertices[] = { Point(10,120), Point(50,120), Point(50,170), Point(25,200), Point(10,170) };
    DrawPrimitives::drawSolidPoly(filledVertices, 5, Color4F(0.5f, 0.5f, 1, 1 ) );
}

When I addChild these layers to a scene and set Z orders 1 and 2, I see that I can bring one primitive on top of another and vice versa - when I exchange the Z order values. The strange things start when I addChild a sprite into one of these layers. If I addChild a sprite, then sprite lays on top of the primitive of that layer, and not only that layer. Even if the layer has smaller Z index, anyway its sprite is on top of other layer's primitive, while its primitive is below the other primitive shape - as was expected. Is this OK? How I should understand this? What if I want to draw primitives on top of all sprites?

EDIT:

I could manipulate their order, but not drawing order, with the following:

CCDirector::getInstance()->setDepthTest(true);
myLayer->setVertexZ(-1);

But I don't understand why sprites in a layer with smaller Z order are being drawn later than the primitives of the layer with bigger Z order. In other words, seems that all the primitives from all the layers is being drawn according to their order, then the same is being done for the sprites.

回答1:

Due to the new multithreader renderer on cocos2d-x 3.0, drawing with primitives requires a different approach. Take a look at my reply at this thread:

https://stackoverflow.com/a/22724319/1468700

回答2:

I believe there is a bug in cocos2d-x V3 beta 2 that makes primitive drawing always appear below all layers. It is fixed (I understand) in V3.0 RC

This is incorrect - there is no bug (I was mislead by other posts - my apologies).

See the post below for a link explaining what needs to happen to get primitives to draw in the 'right' z-order.

The summary is that all drawing operations are added to a queue in the game loop, then the queue processed - so you need to add your primitive drawing into the queue rather than drawing immediately.

来源：https://stackoverflow.com/questions/22288222/primitives-and-sprites-z-index-in-cocos2d-x-3-0-is-not-consistent

标签

cocos2d-x

cocos2d-x-3.0