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Caradavin1
20th Aug 2002, 17:30
Okay, I am pulling my hair out. I have lost/scrapped this dang mission 3 times already and always when I get far. Is there a limit to how many floors a building can have (and it's height?) I made an air brush of 100x256x256 for my overall grounds. Then I built my basically 7-story castle. Things seemed to go great until I moved my StartingPoint to the top floor so I could see my work from another perspective and I get the "Image complexity" (or something similar) error message. Also, what's with the flow brushes??? They usually work good on my complex fountains, but if I do a simple river or standing water, I get an error buff 80 exceeded by 84. AAAAARRRRRRGGGGGHHHH!!!! I'm not giving up, I am now heading to Dromed Central to look up any help I can find, and I will pray that someone can help me.

:eek:

ChangelingJane
20th Aug 2002, 18:44
Is your castle open in any areas? If there's a spot where several floors are exposed, or if a lot of the castle is open to the outside, there might be too many polygons in view for the game to handle. I think that's usually what's going on when you get that error.

Caradavin1
21st Aug 2002, 17:42
Well, the area I moved my StartingPoint to was on the roof, which I airbrushed to be open so my soldiers could patrol it. That could very possibly be the problem. I found ways to reduce polygon count, and I found other helpful items at Dromed Central. But I still can't seem to find out if there is a limit to how tall my building can be. I also wonder if there is a limit to how much taller my worldspace airbrush can be compared to my building. Am I stuck only having a 4-story castle???

theBlackman
21st Aug 2002, 17:47
Originally posted by Caradavin1
Well, the area I moved my StartingPoint to was on the roof, which I airbrushed to be open so my soldiers could patrol it. That could very possibly be the problem. I found ways to reduce polygon count, and I found other helpful items at Dromed Central. But I still can't seem to find out if there is a limit to how tall my building can be. I also wonder if there is a limit to how much taller my worldspace airbrush can be compared to my building. Am I stuck only having a 4-story castle???

I am currently working with a 200 x200 x 200 AIRBRUSH. As the average height per floor is 10 to 15 feet (in a castle maybe 20) you should be able to get contructions as high as you want.

Inside this I am playing with solids to build various things, as yet I am not having a problem with walls up to 80 feet high.

ChangelingJane
21st Aug 2002, 22:54
As theBlackman said, height isn't the problem. You can go as tall as you can wide without Thief screwing up, it can't tell the difference really.

schwaa
22nd Aug 2002, 02:22
You are getting complexity errors, this means your scene is TOO COMPLEX.

Ways to simplify it:

<li>Use one giant brush for the "sky box", if you have four misaligned boxes your scene will increase in complexity quite a bit.
<li>Block lines of site, if you see too far complexity goes up.
<li>Use textures and lights for detail, keep the brush detail as low as possible. If you have really long lines of site keep the terrain very basic. If you are in small cramped areas with short view lengths you can detail with brushes quite a bit.
<li>type <b>show_stats</b> in the text box, then go into game mode <b>Alt-G</b>. there will be a list of stats in the corner. Polycount works best under 250. Some FM's like CL and Hallucinations are probably above 350 which is fine if your computer is really good (or if the players computers are really good).
<li>type <b>show_cells</b>. this will show lines thruout the airspace in your mission. Probably MORE important than polycount. Cells are the "air polys". Dromed uses them to figure out where Ai's and the player can go. If the cells are just big squares theres no prob, if there are tones of black lines all over the place dividing the air into very small slivers you'll need to reduce brush complexity.
<li><b>Snap to Grid</b>. Stay at 14 for MOST details. ONLY go under this for fine details like proper stair height (0.75 units). This is really important, grid MUST be on. the word grid should be purple not white. If you decide not to do this you will get many errors and crashes. You can go smaller but I've found lately I get great results staying at this grid size. Once you learn Drom better you can go a little smaller (13 for major details- 12 or 11 for small deatils in short sight distances) but 14 is good for consistant results and minimal crashes.

Telliamed_
22nd Aug 2002, 05:09
I can't guarantee that what I'm about to say is 100% correct, much less 100% coherent. But I'll try to explain as best I can since I've had some success with it.

Use Blockable brushes to reduce cell splitting.
As schwaa mentioned, cells are "3-d polys".3d engines like to work with convex shapes. If there's something that's concave, it splits it into smaller concave pieces. When you turn on 'show_cell' and look at the flat surfaces of your brushes, you'll see a tesselation of convex polygons. The three-dimensional space is treated the same way, it's just a lot harder to actually see.

When you portalize, Dromed just splits everything up as quickly and easily as it can. The result is a huge number of polys and cells. A lot of those splits aren't necessary, but finding those redundancies takes a lot of work. That's why there's a seperate process for optimizing. It portalizes, then tries to merge adjacent polys and cells while still keeping everything convex.

It's not perfect. And the way some things can be built doesn't help. When you stick a solid brush inside an air brush, it creates a concave shape. The edges of that solid brush are going to radiate out splitting all air brushes the imaginary lines pass through. But an air brush doesn't necessarily have to be affected by some small post 100 units away.

That's (one of) the things blockable brushes are for. The face of a blockable brush acts as a barrier to cell splitting. Any splits occuring inside the blockable brush will not extend outside it -- nor will outer splits reach into the blockable brush.

A blockable brush itself will force splits around it, in that way acting like a solid. But if you align the brush so it's edges fall along already existing cell boundaries, then a blockable brush can be zero-cost.

Example: In the Taffer's Tower, I built a complex staircase. The staircase was in one half of a long airbrush. The stairs were splitting the cells on the far end of the air brush, which also caused splits in adjascent brushes. I drew a blockable brush around the staircase and aligned the edges with the airbrush the near sides of the surrounding air brush. The width of the blockable brush extended far enough to surround the staircase, and was aligned with a nearby brush that was splitting the long air brush crosswise anyway. The result was that half of the long airbrush was able to be merged into a single cell, saving a whole lot of polys.

And that probably makes no sense to you, so just get the mission and see for yourself.

Caradavin1
23rd Aug 2002, 20:37
Thank you!!! I always wondered what blockable brushes were for. There were a couple of things I saw right off that I've been doing wrong. Thank you for the tips everyone.