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View Full Version : compatibility between glslang and video cards and advantages



airseb
01-26-2004, 10:27 AM
does the glslang of the 1.5 version is supported by the geforce 3, 4 and radeon 8500 ?
and what are the advantages of hardware support against the software support of the same effects (not the software emulation but software implementation)except the unloading of the cpu ?

Ostsol
01-26-2004, 05:52 PM
Well, right now only the ATI's Radeon 9500 and higher support it. It doesn't seem likely that there will be support for the Geforce 3 or 4, or for the Radeon 8500 as the spec calls for floating point precision -- which none of those cards has. This is, of course, unless a specialized sub-set of the spec is released to accomodate older cards' capabilities. Somehow I kinda doubt that that will happen, though.

Corrail
01-27-2004, 01:36 AM
No, ATI's 9500 and up doesn't support GL 1.5 fully. EXT_shadow_funcs are not supported by ATI graphic cards.
But nVidia FX series seems to support it and all other GL 1.5 extensions.

GL 1.5 won't be supported fully in hardware by GeForce 3 & 4 and Radeon 8500 because they they are not able to run fragment programs.

Maybe (but I really doubt it) there will be a compiler setting for DX8 cards in some GLslang implemenations.

The advantage of full hardware support is that the CPU doesn't have to do so much. e.g. ARB_vertex_program is available at GeForce 1 & 2 but not in hardware. The result is the same but it is done in software and the CPU has to do the work.

datenwolf
01-27-2004, 01:39 PM
Originally posted by Corrail:
No, ATI's 9500 and up doesn't support GL 1.5 fully. EXT_shadow_funcs are not supported by ATI graphic cards.


Actually OpenGL 1.5 is using ARB_depth_texture and ARB_shadow extensions, which are, according to my glString(GL_EXTENSIONS), present on my Radeon 9800.