ogl red book question

[nobond]

Two basic question on the OGL red book
1. Chapter 3 is talking about when double buffer mode will make the bit plane half compared to the single buffer mode? What is that means? I can only imagine if you really physically have one frame buffer,you have to share this. But in the real world, framebuffer is always always at least double buffered?

2. Is the color index mode very rare to use in these days?

[ProsperLOADED]

Two basic question on the OGL red book
1. Chapter 3 is talking about when double buffer mode will make the bit plane half compared to the single buffer mode? What is that means? I can only imagine if you really physically have one frame buffer,you have to share this. But in the real world, framebuffer is always always at least double buffered?

2. Is the color index mode very rare to use in these days?

Be aware that the Red Book is a bit outdated. Some items in it may hold true for old SGI workstations but not for nowadays GPU.

1. I think it means that if you request a double buffered framebuffer, some implementations may support only half the bit depth it would support if you requested a single buffered framebuffer. AFAIK, it never happens on mainstream GPU : if you request a double buffered framebuffer, the driver just allocates twice as much VRAM for it and you get the same bit depth, whether you use a single or a double buffered framebuffer.

2. AFAIK, it hasn't been supported by any mainstream GPU since the GeForce 256. I don't know for older chips but anyway, it's definitely something you don't have to care about.

[nobond]

Thanks.
Not realise the red-book is so old:grin: