DrawIndexedPrimitive

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1 comment, last by of_ownage 16 years, 7 months ago
hi, i have a question. I have a small application with 16 from .raw heighmap generated raw files. now every of this 16 Meshes has around 130k triangles and if i draw them with frustum cull i get around 33 fps. Now i found out that my application requires 140mb ram and i simplified the meshes. Now i have 16 32.7k triangle terrains. the strange thing is with the 16*130k triangles my app runs at 33 fps with the 16*32k triangle terrains the app runs at 22fps. So my question is, has it something to do with the DrawIndexedPrimivite? I do not see any reasons why it gets slower because 1) i have 4times fewer vertices 2) i have not 1024 bounding boxes to AABB/frustum, now i only have 256 And if the DrawIndexedPrimitive is the problem is there any general amount of vertices i should give this function like for example 2000 or 3000? thx for any help ;)
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How many DIP calls are you making before/after? That can have a big impact.

Also, if you're storing them in ID3DXMesh objects are you optimizing them once you've simplified them? A distinct possibility is that your original code has good post-transform cache utilization and sequential memory reads, but your simplification has destroyed any coherancy and you're not benefiting from these hardware optimizations anymore.

Has anything else changed?

hth
Jack

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Jack Hoxley <small>[</small><small> Forum FAQ | Revised FAQ | MVP Profile | Developer Journal ]</small>

thank you for your help i fixed the problem. Was my own fault i drawed all meshes with full detail and no lod check^^

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