agedboy

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About agedboy

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  1. To [url="http://www.gamedev.net/user/169467-mhagain/"][color="#284b72"]mhagain[/color][/url]: Thanks for your analysis! I didn't know "Each GPU register is 4 floats wide". If it is so, then the situation on GPU side should be similar to CPU side. I mean, vec4 buffer should be, at least, no slower than vec3. Your theory about "The extra memory is clearly being [i][u][u]used[/u][/u][/i]" sounds quite reasonable. Thank you again. To clb: Thanks for your reply. If you get 4xfloat profiled one day, don't forget to share your result
  2. On the other hand, I also think using vec4 vertex buffers really waste the video memory, since I'm actually not using homogeneous coordinates on cpu-side, the extra component of vec4 is just placeholder to let SIMD work. vec3 or vec4, which would you prefer and why? Thanks a lot!
  3. I'm writing OGL programme in its core-profile style. I was using vec3 as vertex buffers (the input attribute of the shader). Now I wanna change to vec4, because I rewrote the cpu-side maths code by sse/sse2. What I'm wondering is whether using vec4 as vertex buffers really slows down the shader programme? I suspect that data stream of vec4 would occupy more bandwidth of the video memory, doesn't it? Thanks!!