On Fri, 2 Jul 2004 16:58:41 +0200 "Nemec, Bernhard" <[EMAIL PROTECTED]> babbled: > Hi, > > i'm writing an application which uses evas to display a gui on an embedded > system. > > Now I'm using a list of lines to draw a curve of measurement values, but > evas_render takes more and more time as more lines are added to the canvas. > I'm therefore looking for an alternative way of drawing a simple curve in > evas. Is it possible to somehow draw the lines into a buffer (kind of a > bitmap image) instead of keeping them as evas_objects, so they wouldn't be > added to the list of objects that evas_render has to go through in every > invocation? yes. evas_object_image_* you can get access to the pixel data of the image and fill it yourself. its all ARGB (from high to low byte, read on a per-32bit word basis - same format imlib2 uses and most PC gfx cards) using lots of lines will slow down - object handling overhead for evas can get very high once you hit a few thousand objects... :( > I also considered using polygons for a moment, but after looking at the > code, I think they will also take more and more time to render as more > points are added. though less overhead than lots of line objects - a lot less. > I very much hope to find a solution to this, because I very much like the > functionality offered by evas for my project. evas can also be extended - the objects are modular (in a way) in that an object type in evas provides some basic methods to evas (like a paint method, pre/post render methods, free meothod etc.) take a look at the simpler objects like line, rectangle, etc. they are very simple and are all in 1 file (evas/src/lib/canvas/evas_object_line.c). as you can see it creates an empty object type then calls the init function to fill the object with that specific type's internals. it shouldn't be hard to make a "polyline" or "curve" object and build it from your own basics and then include it as a "first class" object in evas. i plan on eventually expanding the list of first class objects in evas - jose gonzales is working right now on code for anti-aliases polygons, lines and circles/arcs. i'd want splines/curves too and add radial gradients as well. filter objects are on my list (blur, sharpen, etc.) and more. if you make such a first-class object it will make your own code simpler (all you do now is feed a list of points into the object one - by one - like the polygon object) and the object does the rest. :) > Any thoughts are very welcome. > > Thanks, > Bernhard > > > ------------------------------------------------------- > This SF.Net email is sponsored by BEA Weblogic Workshop > FREE Java Enterprise J2EE developer tools! > Get your free copy of BEA WebLogic Workshop 8.1 today. > http://ads.osdn.com/?ad_id=4721&alloc_id=10040&op=click > _______________________________________________ > enlightenment-users mailing list > [EMAIL PROTECTED] > https://lists.sourceforge.net/lists/listinfo/enlightenment-users > -- ------------- Codito, ergo sum - "I code, therefore I am" -------------- The Rasterman (Carsten Haitzler) [EMAIL PROTECTED] 熊耳 - 車君 (数田) [EMAIL PROTECTED] Tokyo, Japan (東京 日本) ------------------------------------------------------- This SF.Net email is sponsored by BEA Weblogic Workshop FREE Java Enterprise J2EE developer tools! Get your free copy of BEA WebLogic Workshop 8.1 today. http://ads.osdn.com/?ad_id=4721&alloc_id=10040&op=click _______________________________________________ enlightenment-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/enlightenment-users
