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Conference bulova::decw_jan-89_to_nov-90

Title:	DECWINDOWS 26-JAN-89 to 29-NOV-90
Notice:	See 1639.0 for VMS V5.3 kit; 2043.0 for 5.4 IFT kit
Moderator:	STAR::VATNE

Created:	Mon Oct 30 1989
Last Modified:	Mon Dec 31 1990
Last Successful Update:	Fri Jun 06 1997
Number of topics:	3726
Total number of notes:	19516

3083.0. "XCopyPlane on RISC server" by ALLVAX::PHILBRICK () Mon Jul 16 1990 17:30

Hi,

Searched but couldn't find any info on this.

I have an application that generates an 8 bit 512x512 raster image on the client.
The image is actually a composite of 8 one bit images that were created using a 
plane mask. My objective is to have high performance monochrome animation by 
individually displaying each plane in the image on the server. Originally 
we created a server pixmap of the image and blasted each plane to the screen 
with an XCopyPlane and a mask. This works fine on VMS servers but was pitifully
slow on the RISC server. Our fix was to copy the raster to an 8 bit server 
pixmap then strip out each plane with a XcopyPlane to (8) one bit deep 
server pixmaps then we free the original 8 bit server pixmap. This leaves us 
with eight one bit server pixmaps that we blast up to the screen with an 
XCopyPlane. The animation is then acceptable on both the VMS and RISC servers. 
Unfortuately the set up still takes a long time on the RISC and seems to be the
XCopyPlane from an 8 bit to a one bit image. It's probably obvious to someone
who knows the RISC hardware what the problem is. 

Any ideas,

Geoff

T.R Title User Personal
Name Date Lines

3083.1 RISC vs CISC vs Graphics H/W ALEXWS::ALEX Bugs are coming in triplets ... Wed Jul 18 1990 03:52 27

T.R	Title	User	Personal Name	Date	Lines
3083.1	RISC vs CISC vs Graphics H/W	ALEXWS::ALEX	Bugs are coming in triplets ...	`Wed Jul 18 1990 03:52`	27
	RE .0 > This works fine on VMS servers but was pitifully slow on the RISC server. >Any ideas, > I bet you are using DS3100 or DS5000-CX, i.e. color frame buffer RISC server. A year ago I wrote a benchmark program for one of our customers that did more or less the same thing you do. As a VMS person that does not want to learn vi and various cc options, I wrote the program on a good old slow VS-II/GPX and then ran it on a DS3100. Indeed the results were rather confusing. Plane copy on GPX (done in H/W BITBLT) were lighning fast and on DS3100 (done in S/W with unpacking the bits and moving them) were as slow as turtle. I do remember that on RISC it took around 20 seconds !!! I think that here one see the differences between RISC, CICS and graphics hardware. Co-Processor boards MUST do BITBLT very very fast. In particular faster than the vertical synch of the monitor, i.e. 1/60 of a second. On RISC frame buffer it takes a lot of operations to unpack the bits and then move them onto the screen. I think that this is the explanantion. But then I might be wrong. Cheers, Alex

	RE .0

> This works fine on VMS servers but was pitifully slow on the RISC server.

>Any ideas,
>

	I bet you are using DS3100 or DS5000-CX, i.e. color frame buffer RISC
server. A year ago I wrote a benchmark program for one of our customers that did
more or less the same thing you do. As a VMS person that does not want to learn
vi and various cc options, I wrote the program on a good old slow VS-II/GPX and
then ran it on a DS3100. Indeed the results were rather confusing. Plane copy on
GPX (done in H/W BITBLT) were lighning fast and on DS3100 (done in S/W with
unpacking the bits and moving them) were as slow as turtle. I do remember that
on RISC it took around 20 seconds !!!

	I think that here one see the differences between RISC, CICS and
graphics hardware. Co-Processor boards MUST do BITBLT very very fast. In
particular faster than the vertical synch of the monitor, i.e. 1/60 of a second.
On RISC frame buffer it takes a lot of operations to unpack the bits and then
move them onto the screen.

	I think that this is the explanantion. But then I might be wrong.

	Cheers,
		Alex