Q: what's faster in VRAM Same tpage?

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gwald
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Q: what's faster in VRAM Same tpage?

Post by gwald » May 22nd, 2017, 11:45 am

1: A large single 120x 24 GsSprite, which is mostly blank (transparent)
2: Or 2 smaller 24x24 GsSprites

I know in openGL, #2 is faster, but I know LibGS has render call overheads.
Anyone know?
Last edited by gwald on May 22nd, 2017, 7:35 pm, edited 1 time in total.

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Shadow
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Re: Q: what's faster in VRAM?

Post by Shadow » May 22nd, 2017, 4:25 pm

Well if you have one large image, the PSX doesn't have to reference so many positions in the framebuffer, so in theory, that would be the quickest. Usually less instructions means the system will execute quicker. Don't think you'll know for sure though unless you compare with a DTL-H2700.
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Re: Q: what's faster in VRAM Same tpage?

Post by Orion_ » May 22nd, 2017, 9:17 pm

try to bench it.
display 100 sprites with method 1 then using method 2, and measure it using the value returned by Vsync.

GsSortSprite_WithMethod1();
cpu_time = VSync(1);
DrawSync(0);
gpu_time = VSync(0);
GsSwapDispBuff();
...
Retro game development on Playstation and other consoles http://orionsoft.free.fr/

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gwald
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Re: Q: what's faster in VRAM Same tpage?

Post by gwald » May 23rd, 2017, 3:23 pm

Cool, thanks both for the replies

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