{"action":"created","issue":{"url":"https://api.github.com/repos/dividuum/info-beamer/issues/29","labels_url":"https://api.github.com/repos/dividuum/info-beamer/issues/29/labels{/name}","comments_url":"https://api.github.com/repos/dividuum/info-beamer/issues/29/comments","events_url":"https://api.github.com/repos/dividuum/info-beamer/issues/29/events","html_url":"https://github.com/dividuum/info-beamer/issues/29","id":95950315,"number":29,"title":"use core profile OpenGL","user":{"login":"vliaskov","id":330408,"avatar_url":"https://avatars.githubusercontent.com/u/330408?v=3","gravatar_id":"","url":"https://api.github.com/users/vliaskov","html_url":"https://github.com/vliaskov","followers_url":"https://api.github.com/users/vliaskov/followers","following_url":"https://api.github.com/users/vliaskov/following{/other_user}","gists_url":"https://api.github.com/users/vliaskov/gists{/gist_id}","starred_url":"https://api.github.com/users/vliaskov/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/vliaskov/subscriptions","organizations_url":"https://api.github.com/users/vliaskov/orgs","repos_url":"https://api.github.com/users/vliaskov/repos","events_url":"https://api.github.com/users/vliaskov/events{/privacy}","received_events_url":"https://api.github.com/users/vliaskov/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":2,"created_at":"2015-07-19T21:25:53Z","updated_at":"2015-07-31T11:22:45Z","closed_at":null,"body":"This is more a of a question, not an actual issue / bug report:\r\n\r\nI 've noticed immediate mode /compatibility profile is used in the code (e.g. glVertex in image.c, video.c rendering). Can these be replaced with core profile OpenGL e.g. VBOs? Do you expect a performance increase if this is attempted i.e. would a version using non-compatibility OpenGL 3.0 offer better performance than the current github version (for PC hardware)?\r\n\r\nAlso: In general it would be useful for volunteers to have a TODO file for possible performance optimizations (such as this question) and for new features."},"comment":{"url":"https://api.github.com/repos/dividuum/info-beamer/issues/comments/126658386","html_url":"https://github.com/dividuum/info-beamer/issues/29#issuecomment-126658386","issue_url":"https://api.github.com/repos/dividuum/info-beamer/issues/29","id":126658386,"user":{"login":"vliaskov","id":330408,"avatar_url":"https://avatars.githubusercontent.com/u/330408?v=3","gravatar_id":"","url":"https://api.github.com/users/vliaskov","html_url":"https://github.com/vliaskov","followers_url":"https://api.github.com/users/vliaskov/followers","following_url":"https://api.github.com/users/vliaskov/following{/other_user}","gists_url":"https://api.github.com/users/vliaskov/gists{/gist_id}","starred_url":"https://api.github.com/users/vliaskov/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/vliaskov/subscriptions","organizations_url":"https://api.github.com/users/vliaskov/orgs","repos_url":"https://api.github.com/users/vliaskov/repos","events_url":"https://api.github.com/users/vliaskov/events{/privacy}","received_events_url":"https://api.github.com/users/vliaskov/received_events","type":"User","site_admin":false},"created_at":"2015-07-31T11:22:45Z","updated_at":"2015-07-31T11:22:45Z","body":"Sorry for the delay. Thanks for the feedback and for the blog post about performance, it's a very useful read.\r\n\r\nPerhaps freetype-gl https://github.com/rougier/freetype-gl  can be used instead of ftgl so that we can create an atlas and use VBOs . Did you implement your own caching on a per string/text basis, or is there some glyph cache provided in a library you use for font rendering in the pi version?\r\n\r\nI also tried the latest font rendering commit edf6d83c (using texturefonts instead of polygonfonts). There is a difference in CPU load (much less load with texturefonts) Fps is the same, about ~60fps on high-end PCs (i.e. framerate was good even before the change, but maybe that's because I am testing simple nodes with not much text). By the way do you measure fps from lua and/or lua callbacks or in another way ? E.g. I 've added code to font_write for font framerate calculations but maybe info-beamer has a generic way of measurement?\r\n\r\nSome of the x86_64 systems I will be testing on have mobile graphics with no dedicated GPU memory, so perhaps optimizing GPU transfers would make a difference.\r\n\r\nIf the other 2 optimizations in the performance blog post are relevant to the github PC version (optimizing MVP matrix and rendering directly to screen instead of an intermediate texture), let me know."}}