don't 10% understand brushes

Blitz3D Forums/Blitz3D Programming/don't 10% understand brushes

Kalisme(Posted 2004) [#1]
Hmmm.... Ok.. this is actually quite embaressing...
I've been a happy blitz owner for a few years...
And I've figured out how to put together
Rigid physics engines and ragdoll from scratch...
So I do have some skill... But I noticed that I've
never really played too much with brush commands...
(not really :( )
Could NEone give me some help... Explain them to me...
And can I use these for Dynamic Lighting?
I still can't do unreal or Quake3 style lighting...
Please help me...


Tom(Posted 2004) [#2]
I rarely use the Brush commands as most if not all my meshes I create in a 3D modeler, so offhand, I don't know much about them neither :)

As for dynamic lighting there's 2, maybe 3, ways to do it.

(I'm no expert so anyone's welcome to correct me :)

Lightmapping: This is where you have a second texture map that's used to adjust the brightness of the actual 'color' map, dynamicaly changing lightmaps is very demanding though, and I don't think it's viable for realtime use.

Vertex lighting: Instead of using a texture lightmap to adjust brightness, you can use Vertex colors. It's much faster than lightmapping, but the downside is your meshes should be well subdivided to create realistic lighting.

The last method is really only suitable for stuff like torchlights hitting walls. You would have a quad poly or maybe a sprite, and change it's blend mode to Multiply and then apply a greyscale texture to it. It does a similar thing to lightmapping, it would change the brightness of anything rendered behind it according to its greyscale texture map.

All these method work on the same principal of have a normal textured mesh, and changing the brightness of that texture via a lightmap texture or vertex color.


If you're just after a way to lightmap a level (quake style), then check the code archives, I think there's some lightmapping programs there.

There's also (to name but a FEW!)

Blitz Researches Maplet (a CSG modeler & lightmapper):
http://www.blitzbasic.com/Products/maplet.php

Cartography Shop (a CSG modeler & lightmapper):
http://cartographyshop.thegamecreators.com

BSP Factory (lets you convert lightmmaped Q3 levels to B3D format):
http://www.bspfactory.tk

Giles[s], a quality radiosity lightmapper (gets my vote!)
http://www.frecle.net/giles


I better stop now, coz I'm rambling! :)
Tom


WolRon(Posted 2004) [#3]
Quoting the reference:
A brush is a collection of properties such as Colour, Alpha, Shininess, Texture etc that are all stored as part of the brush. Then, all these properties can be applied to an entity, mesh or surface at once just by using PaintEntity, PaintMesh or PaintSurface.


of course, I'm sure you already knew that though...


Kalisme(Posted 2004) [#4]
Thanx... I use Maplet...
I was refuring to the dynamic real-time lighting,
gun flashes like off unreal or Quake III...
I've tried different methods... But I can't
seem to actually subtract from the shadows...
arggg!
Thanx for ur help :D


Dreamora(Posted 2004) [#5]
What you mean are decals.


Kalisme(Posted 2004) [#6]
ok... kewl
thanx :D