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RRA | 13 years ago | 2 comments | 2,265 views

Hi Michiel,

Is it possible to compose scene where :
- texts are located like digits/hours on watch plate
- under each text is located his mirror (as text object rotated and moved a little bit to simulate floor thickness)
- watch plate (floor) is made from circular white to tranparent gradient as picture layer (tranparency strong on border)
- all packed to containter
- container is in motion (entire turn)
- camera is looking on scene as in acsonometric.

I have faced with problem, that during motion of container, mirrors of text (copied and rotated layers) are DISAPPERING. It's not possible to keep all mirrored texts visible.

Michiel, you have answered, that this is problem of sorting objects with transparency and :

"BT sorts layers by their centre position" ?

Could you describe this problem more precisely ? Hot to overcome this obstacle ? Or how to create partially transparent floor layer in order to avoid problems with objects which are located under the floor ?




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Modern graphics cards can render millions of triangles per second, but they still can't handle transparency well.

Transparent triangles needs to be rendered back to front according to their distance to the camera. Graphics cards can't do this sorting so it has to be done by software, in this case by BluffTitler.

To do it right all transparent triangles of all layers needs to be sorted. As you can imagine this can take a lot of time and seriously slow down the rendering speed.

As a compromise BluffTitler only sorts the layers. This is super fast and most of the time gives the desired result. In some cases however, especially when using small layers in combination with big layers (like huge picture layers) sorting errors can occur.

The picture layer of version 8.1.0.3 features a Z-BIAS property. This property can be used to artificially adjust the distance to the camera and in this way changing the sorting order. For example setting this value to
-100 makes sure the layer is rendered last.

michiel, 13 years ago


Hi,

Thank you, -100 was not enough but -300 and problem solved.

Additionally : keeping floor layer out of main container also helps a little bit.

RRA, 13 years ago

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