drawing text decreases perfomance.

Question

Hi all. I'm developing a 2D drawing application, where one of the tasks is add text, than can be rotated and fonts selected. The problem is that, when there is a amount of about 50 texts drawn, the application becomes very slow. This happens only with text, because with lines, polygons and circles the perfomance is not significantly modified. Has someone any ideas of this problem´s origin? Is GDI+ so slow with texts and fonts?. Thanks in advance.

Mykonine · Answer

You could try using unmanaged code to do your graphics processing. That should greatly speed up the process.

asimancas · Answer

Yes nobrainer. I have spent the whole day researching about DirectDraw to finally realize that it´s deprecated. I´ll rather try to optimize the visualization on my application (keeping GDI+) because seems to me DirectX is too much deep for what i have in mind (2D vector drawing) although it can work with 2D. Nevertheless i think is unfair that GDI+ be so slow. :-(. Perhaps i´ll have to move towards some space partitioning. Thanks.

bilnaad · Answer

ps. With the Latest DirectX DirectDraw doesn't exist anymore. All functionality of DirectDraw is implemented into Direct3D

bilnaad · Answer

Also the since windows 2000 directX is intergrated into the installation of windows. So it's on the user's machine by default.

robin 0 · Answer

It depends on what kind of users your programm is oriented... Most of users now has installed DirectX on their comps... but of course if you'll make your programm fast without it - it'll be better... But I just do not know the way to do it so...

asimancas · Answer

Hey Robin. I was rethinking about DirectDraw: Maybe will be overkilling ask to the potential users to get installed in their PCs DirectX just for running my application. Don´t you think so?. Does someone know what´s de graphics engine of programs like Autocad?. Till i know they don´t use DirectX may be some APIS?. Thanks again.

asimancas · Answer

Well i´ll try DirectDraw. I think there is not problem with the application startup (hope so). thanks for your replies. Regards.

robin 0 · Answer

DirectX is not for 3D mainly. It's a system of direct access to multimedia hardware. So Direct3D - direct accesss to 3D accelerator card DirectSound - sound card DirectDraw - 2D methods of drawing directly in graphical card. In your case the only thing you need - DirectDraw. And in this case it will increase perfomance of application but application startup time will increases too.

asimancas · Answer

Thanks for reply. so what should i do?. Won´t be posibble to build a complete drawing application with GDI+?. It can be don with DirectX? but i understand that this is for 3D mainly. Thanks again.

Mykonine · Answer

GDI is famously slow. Right now I have a program that generates my desktop background as a schedule and homework assignment manager and with the fifty or so text entries it usually takes around 3 seconds to create the file save and change backgrounds.