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Indexed POINTLIST not available..then?

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Hi... I am working under DX7, and found that DrawIndexedPrimitiveVB() call is not usable with POINTLIST primitive types... then...? I mean... Can I use the same function passing other parameters...? in this case what for the Index list, a list just filled of sequential indexes...? Can I only use the non indexed DrawPrimitiveVB() call...? could any1 make it more clear to me...? tnx [R]ed

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The documentation for IDirect3DDevice7::DrawIndexedPrimitiveVB states that:
d3dptPrimitiveType
Type of primitive to be rendered by this command. This must be one of the members of the D3DPRIMITIVETYPE enumerated type.
The D3DPT_POINTLIST member of D3DPRIMITIVETYPE is not indexed


Basically, you can use indexing with other primitive types, but not with points. The reason behind this is that indexing buys you nothing with points, it actually adds a cost. Indexing is used to save bandwidth and memory by not repeating vertices that appear more than once, as well improving cache performance - This makes sense when you're working with triangles, where often a single vertex is shared by more than one triangle. However, when using points, you can guarantee that:
1) You won't be drawing the same point twice (Makes no sense)
2) No repitition at all
3) Using indices would add the cost (memory and time) of storing indices and reading them.

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Yep...
Tnx Coder...
I know Indexing will give nothing more with points, even if this is not fully true... I could use same indexes of triangle vertices to make there different color points with some options... saving memory in an application drawing a lot of items...

however... how u pointed out... DX Docs dont say 'U CAN NOT USE D3DPT_POINTLIST with indexed draw calls'... so...basically... I was just wondering if there is any way to use a PointList with an indexed primivive draw call...

tnx

[R]ed

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