From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 In-Reply-To: References: <7caa7a0a-fb6d-4ffa-81ef-ad3256100f2c@g21g2000yqk.googlegroups.co> <9e5fc5ec-43d5-4cf3-be92-3fc8c4829ba0@l32g2000yqm.googlegroups.co> From: Venkatesh Srinivas Date: Sat, 1 May 2010 18:48:48 -0400 Message-ID: To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: text/plain; charset=UTF-8 Subject: Re: [9fans] ctrl radeon: not working for ATI Radeon 9600 Mobility? Topicbox-Message-UUID: 16f52bd0-ead6-11e9-9d60-3106f5b1d025 > [...] the main slowdown > is reading from the hardware framebuffer, which plan 9 does a lot. Where in the draw path does Plan 9 read back from the framebuffer? Why so much? Also, there is apparently a fast way to read-back on radeon series h/w - map some system memory on the card via the GART and do the same dance that drm's r100_copy_blit does. If the formats are amenable, it might be nice to expose cards' fast download-from-screen features, by adding something like Ctrl->dfs() or the like... -- vs