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lisa · 23rd May 2007, 04:34 PM

- Different display methods(wireframe only, solid...)

This effect frame rate--often significantly--but generally not memory consumption.

- Use of textures
- Texture size

Textures are usually the number one source of memory consumption in any 3D application. Textures often consume more memory than the geometry, especially in modern applications that use many different types of maps on a single model. (i.e. diffuse, specular, normal, etc.)

- Amount of triangles, and how many of them share vertices

This is polycount. Number of shared vertices matters, but not as much as other factors.

- Display size, the bigger the more pixels have to be calculated

Again, this effects frame rate, but not memory per-se unless frame buffer calculations are done in software instead of hardware. Possible, but not common these days.

Note: by memory, I mean "main memory", aka RAM. A large frame buffer does of course effect video memory, often significantly, as it increases both the visible buffer as well as the back buffer, stencil buffer and z-buffer.

- anisotropic filtering, antialias n such stuff

Again, unless this is being done in software on the CPU, these will effect frame rate but not (main) memory consumption. Whether or not they effect video memory usage is dependent on the algorithims used.

Technically, while anisotropic filtering is very GPU intensive, and may use more video memory *bandwidth*, total consumption can actually often be reduced becase the better filtering means lower-resolution textures can be used.

23rd May 2007, 04:34 PM	#10
lisa Senior Member Professional user Join Date: Mar 2005 Location: Phoenix, AZ Posts: 917	Re: large size? - Different display methods(wireframe only, solid...) This effect frame rate--often significantly--but generally not memory consumption. - Use of textures - Texture size Textures are usually the number one source of memory consumption in any 3D application. Textures often consume more memory than the geometry, especially in modern applications that use many different types of maps on a single model. (i.e. diffuse, specular, normal, etc.) - Amount of triangles, and how many of them share vertices This is polycount. Number of shared vertices matters, but not as much as other factors. - Display size, the bigger the more pixels have to be calculated Again, this effects frame rate, but not memory per-se unless frame buffer calculations are done in software instead of hardware. Possible, but not common these days. Note: by memory, I mean "main memory", aka RAM. A large frame buffer does of course effect video memory, often significantly, as it increases both the visible buffer as well as the back buffer, stencil buffer and z-buffer. - anisotropic filtering, antialias n such stuff Again, unless this is being done in software on the CPU, these will effect frame rate but not (main) memory consumption. Whether or not they effect video memory usage is dependent on the algorithims used. Technically, while anisotropic filtering is very GPU intensive, and may use more video memory bandwidth, total consumption can actually often be reduced becase the better filtering means lower-resolution textures can be used.