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DataGame

OpenGL Howto animate Bitmap Font

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DataGame    100
Hi! I am using FTGL to display Text via OpenGL. I tried all the FTGL rendering modes: * Bitmaps * Anti-aliased pixmaps * Texture maps * Outlines * Polygon meshes * Extruded polygon meshes And noticed that Bitmaps have the lowest data volume (PC-RAM -> VGA-RAM). This is important because i use OpenGL over the network. It all works fine but now i need to animate the Bitmap-Text (Paint it on a cube and rotate the cube). Do you have an idea? * Is it possible to 3D-Animate this Bitmap-Text? * Is it possible to use another rendering mode and load the data in a compressed format to the VGA-RAM? * Is it possible to antialias Bitmap Font in VGA-RAM? * I also want to up-/downscale the scene. How can i achieve a good font quality at most scaling factors?

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Lord_Evil    680
AFAIK bitmap fonts are directly blitted to the frame buffer, i.e. rotating, scaling, antialiasing etc. would not be possible using OpenGL. You'd have to calculate the appropriate bitmaps yourself.

You might instead use texture mapped fonts and either send compressed textures/atlases or only send the characters and use textures on the server.

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DataGame    100
Quote:
Original post by Lord_Evil
You might instead use texture mapped fonts and ... send compressed textures/atlases ...

Can you please give me a hint how to do it?

Thanks! :-)

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Lord_Evil    680
I assume you send the texture data over to your server, render your scene there and then send the rendered image back to the client?

If so, you might just send the texture atlas in some compressed format (like DXT) and later just send the text along with some font id (which is related to the texture).

IIRC you may compress a texture by loading it into video memory and setting a compressed format for it. The driver then will handle compression. Afterwards you read the compressed data back into your client memory. This assumes you run OpenGL on your client as well, if not you'd have to implement the compression algorithm yourself (or use another one like JPEG2000).

Edit:

A basic approach could be

- compress texture on client
- send texture to server, receive font id
- for each frame
- send text and font id
- render text using the specified font on server
- receive rendered image

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