pjd2@po.CWRU.Edu (Pedro J. Diaz) (05/01/91)
Can someone tell me what the pixel format for the GRX or CRX frame buffers is. (i.e. what is the 8 bit pixel format for pseudocolo, is it 8 bit out to an 8,8,8 pseudo RAMDAC or is it organnized as 3,3,2 or ?????) Thanks -- Pedro J. Diaz, Ph.D. | CWRU School of Engineering/School of Medicine PO Box 21560 | Department of Biomedical Engr. & Radiology Cleveland OH 44121 | MetroHealth Hospital (216)-459-4958
stroyan@hpfcso.FC.HP.COM (Mike Stroyan) (05/05/91)
> Can someone tell me what the pixel format for the GRX or CRX > frame buffers is. (i.e. what is the 8 bit pixel format for pseudocolo, > is it 8 bit out to an 8,8,8 pseudo RAMDAC or is it organnized as 3,3,2 > or ?????) > Pedro J. Diaz, Ph.D. | CWRU School of Engineering/School of Medicine The CRX display has 8 bits per pixel. Each pixel index is mapped through color map to red, green, and blue intensity. There are 8 bits for each of red, green, and blue. The GRX display just maps each index to one grey intensity. One wrinkle on this is that there are actually 16 frame buffer planes arranged into two 8 plane banks to allow double buffering. There is another plane which selects which bank is displayed on a pixel by pixel basis. This allows independent double buffering of multiple windows in X. The bank select feature is not supported directly by the X server. It is only accessible through the Starbase or PHIGS graphics libraries. Mike Stroyan, mike_stroyan@fc.hp.com