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A gaming and technology blog by TWHL admins Penguinboy and Ant. A music blog by TWHL users Ant and Hugh.

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avatar Striker 22nd March 2017, 11:13 AM

Hammer, although having a spartanic interface, is still a role model for other level editors through its common sense. And this, after almost 20 years from its conception.

2016 GDC talk


avatar Penguinboy says: 23rd March 2017, 00:06 AM
Hey, this looks relevant to my interests, especially since I've started working on Sledge again. I will watch it when I have some spare time I'm at work. Thanks!

Edit: Interesting watch. The ideas of creating geometry in Unreal/3DS are really cool. Will have to keep that in mind for Sledge!
avatar Tetsu0 says: 25th March 2017, 13:24 PM
If you can make subtractive geometry work for sledge i think I'll fly to Australia and give you a hug
avatar Bruce says: 25th March 2017, 15:12 PM
i have heard countless times of people saying how horrible geometry is in unreal compared to hammer
avatar Crollo says: 26th March 2017, 00:57 AM
Perhaps the simpler nature of additive brush building might appeal to a beginner, but gain any amount of experience and the flexibility of subtractive geometry becomes very apparent. Only having to manage the faces of geometry that will actually exist/be visible in your level, much faster iteration time as well as readability of your levels since you don't have to see all the extra geometry (in your 2d views) that won't exist in the final level and is not relevant.

I can't speak to final performance in the compiled BSP as I am not technically privy to what goes on under the hood, but at least for the source map file you will see significantly reduced filesizes.
Consider a simple room: In subtractive, it's 8 vertices with 6 faces, corresponding to only the vertices and connecting faces that make up the inside (and relevant portion) of the room.
In additive, it's 48 vertices with 36 faces, which corresponds to the inside vertices and faces of the room, as well as all of the outer faces and vertices of the 6 boxes that make up the room.
That is 6 times the information, most of which contains wasted UV space, texture and position data, as well as any other information that can be mapped to the unnecessary vertices and faces within hammer itself.
avatar Penguinboy says: 26th March 2017, 01:08 AM
Eh, the only way (that I can think of) to implement a subtractive -> bsp process would be to carve, so it's probably never happening for GS/Source editing.
avatar Admer456 says: 26th March 2017, 07:26 AM
And... what about texture alignment? I played Unreal yesterday and everything looked so seamed on the edges of cliffs and terrain.
avatar Archie says: 26th March 2017, 09:27 AM
Finally got round to watching this - very interesting. Thanks for sharing!
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