{"action":"created","issue":{"url":"https://api.github.com/repos/hzeller/rpi-rgb-led-matrix/issues/69","labels_url":"https://api.github.com/repos/hzeller/rpi-rgb-led-matrix/issues/69/labels{/name}","comments_url":"https://api.github.com/repos/hzeller/rpi-rgb-led-matrix/issues/69/comments","events_url":"https://api.github.com/repos/hzeller/rpi-rgb-led-matrix/issues/69/events","html_url":"https://github.com/hzeller/rpi-rgb-led-matrix/issues/69","id":110759211,"number":69,"title":"text aliasing of led-matrix -D 1 or 2 on 32x32","user":{"login":"yarikoptic","id":39889,"avatar_url":"https://avatars.githubusercontent.com/u/39889?v=3","gravatar_id":"","url":"https://api.github.com/users/yarikoptic","html_url":"https://github.com/yarikoptic","followers_url":"https://api.github.com/users/yarikoptic/followers","following_url":"https://api.github.com/users/yarikoptic/following{/other_user}","gists_url":"https://api.github.com/users/yarikoptic/gists{/gist_id}","starred_url":"https://api.github.com/users/yarikoptic/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/yarikoptic/subscriptions","organizations_url":"https://api.github.com/users/yarikoptic/orgs","repos_url":"https://api.github.com/users/yarikoptic/repos","events_url":"https://api.github.com/users/yarikoptic/events{/privacy}","received_events_url":"https://api.github.com/users/yarikoptic/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":10,"created_at":"2015-10-10T01:22:32Z","updated_at":"2015-10-11T23:23:50Z","closed_at":null,"body":"Thanks for the project and detailed HOWTO -- getting 32x32 (6mm pitch) from adafruit  running (using old PC power supply for 5V) was quite easy (ultimately need to chain 4).  All demos seems to work nicely **but** the scrolling text -- my primary target.  What could lead to text aliasing such as shown at http://www.onerussian.com/tmp/LED-text-aliasing.jpg .  Usually it just aliases to the right (up to 3 LEDs) and if there is an extended number of light up LEDs seems sometimes happen to the left LEDs as well.  The effect of right aliasing is independent from direction of text scrolling (-D 1 vs 2) -- guaranteed aliasing to the right.  I have tried rebuilds with varying values for `DEFINES+=-DRGB_SLOWDOWN_GPIO=1` which seemed had no effect.  Static text (text-example) shows beautifully.\r\nAny advice on where should I dig to manage to avoid having such aliasing effect?"},"comment":{"url":"https://api.github.com/repos/hzeller/rpi-rgb-led-matrix/issues/comments/147255056","html_url":"https://github.com/hzeller/rpi-rgb-led-matrix/issues/69#issuecomment-147255056","issue_url":"https://api.github.com/repos/hzeller/rpi-rgb-led-matrix/issues/69","id":147255056,"user":{"login":"hzeller","id":140937,"avatar_url":"https://avatars.githubusercontent.com/u/140937?v=3","gravatar_id":"","url":"https://api.github.com/users/hzeller","html_url":"https://github.com/hzeller","followers_url":"https://api.github.com/users/hzeller/followers","following_url":"https://api.github.com/users/hzeller/following{/other_user}","gists_url":"https://api.github.com/users/hzeller/gists{/gist_id}","starred_url":"https://api.github.com/users/hzeller/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/hzeller/subscriptions","organizations_url":"https://api.github.com/users/hzeller/orgs","repos_url":"https://api.github.com/users/hzeller/repos","events_url":"https://api.github.com/users/hzeller/events{/privacy}","received_events_url":"https://api.github.com/users/hzeller/received_events","type":"User","site_admin":false},"created_at":"2015-10-11T23:23:50Z","updated_at":"2015-10-11T23:23:50Z","body":"Ah, yes, that is what I meant - a typo.\r\n\r\nThe API documentation should be explaining what is happening. If you think of standard animation, this is essentially double-buffering.\r\nYou create an off-screen buffer, fill that, and then swap it with the other buffer. Then you can write on the new offscreen buffer (that SwapOnVSync() returned) and start over."}}