Patch Thickening

[greebo]

This feature was relatively easy to implement (apart from a little confusion on my side regarding patch rows/columns vs. width/height which cost me nearly two hours ):

 

 

The dialog looks like this (the thickening affects all selected patches btw):

 

What's left is a code cleanup and some testing.

[OrbWeaver]

Some pretty funky shapes there, especially in the bottom picture. How does it calculate the "thickness", is it extruding the patch along its normal vectors or what?

[SneaksieDave]

Oh holy shit.

 

Edit:

Some pretty funky shapes there

Indeed, I'm assuming those were distorted after construction? Or maybe not, considering the explanation below.

 

We'll see soon enough. Can't wait to try this one out.

[greebo]

Some pretty funky shapes there, especially in the bottom picture. How does it calculate the "thickness", is it extruding the patch along its normal vectors or what?

Exactly. Two adjacent control vertices are taken into consideration for the normals, which allows the thickened counterpart to follow the shape of the source patch.

 

@SneaksieDave: I will upload a new build for you, you can check it out soon.

[sparhawk]

That looks like a really cool and usefull feature.

[greebo]

SneaksieDave, here is another snapshot, just extract it over the previous one you downloaded yesterday:

 

http://208.49.149.118/TheDarkMod/download/....8.x.rev962.zip

[SneaksieDave]

Thanks! Got it.

 

Here's the result of my first official DarkRadiant thickened patch (there's a small issue which results in some distortion of it, but it looks like a simple problem - image is before/after a tiny amount of vertex manipulation):

 

Will let you know if I come across any other issues of course.

[PinkDot]

Very useful thing! It would be even better if we could choose among extruding along normals computed for each vertex separately (just like it does now) or one common direction or X, Y or Z axis.

[greebo]

Very useful thing! It would be even better if we could choose among extruding along normals computed for each vertex separately (just like it does now) or one common direction or X, Y or Z axis.

This sounds useful as well, I'll put that in the features wanted list.

[greebo]

Ok, that one was not too hard to implement:

 

 

One disadvantage of having a fixed extrusion axis is that the resulting patches may be inverted (and invisible for the first moment), but that is already covered in another issue (rendering patches as wireframe from behind).

[OrbWeaver]

Here's the result of my first official DarkRadiant thickened patch (there's a small issue which results in some distortion of it, but it looks like a simple problem - image is before/after a tiny amount of vertex manipulation):

 

I noticed that distortion when I tried it -- surely the vertex lines shouldn't cross over like that? Could there be a bug in the normal-calculation code?

[greebo]

Could you show me an example of such a patch, I'd like to look into that. I already though about taking a "mean" normal vector, as there are 4 available (at most, for a vertex surrounded by four nearest neighbours).

[SneaksieDave]

It's easier than you think. Just create a cube and make a bevel from it. Thicken that and the result above is given. Fixing it is just a matter of pulling two vertices down. It worked fine everywhere else, just not at the midpoint of the curve.

 

Ok, that one was not too hard to implement:

Holy cow.

[greebo]

Ok, I just followed your instructions, but I didn't get a weird patch out of it. This is what I did:

 

Created a cube:

 

Clicked: Curve > Bevel, then deleted the cube:

 

Then thickened the thing (first with thickness 16, then undid that one and thickened it with thickness 100):

 

What did I wrong?

[OrbWeaver]

I think your second thickened patch is displaying the behaviour -- notice how it gets thinner in the middle and the lines in the "side wall" go diagonally. If it was extruded along the normal, I would expect both the start and end patches to be parallel at all points.

[SneaksieDave]

Yep, but it actually looks like the first has a problem too. I probably should have specified a thickness, so that it's easiest to see. It's hard to tell if it is warping down in the first pic (which would be much more troubling), or back toward the camera, but based on the known behavior, I assume it's back toward the camera. Instead of the normals being perpendicular to the surface, they're collapsing back toward the viewer.

 

My original image above shows not just the before/after fix, but could also be seen as DR/DoomEd. The image on the right is what DoomEd builds.

 

Probably the easiest way to see it is a square - all sides equal.

 

Edit: In fact, looking at my original image and considering the basis for the original patch to be a square, and looking at the control points, it speaks to how it is built. It looks like two control points are placed on the endpoint edges, each half of the desired thickness inward (away from the surface), and then at the corner point, the same is done diagonally.

[greebo]

Ah, thanks, I can see it now. I'll see what I can do about this.

[greebo]

Ok, hopefully I've got it right this time:

 

I had to tweak the normal calculation a bit, taking the average vertex normal. The resulting normal had to be scaled as well, which reminded me a bit of the derivation of Fresnel's law.

 

There is still an issue with thickening end caps, which is perhaps a completely different issue, I'll have to check that

 

edit: the snapshot is here: http://208.49.149.118/TheDarkMod/download/....8.x.rev968.zip

[SneaksieDave]

Beeeautiful. Using the same bevel twice, once thickened inward, the other, outward (with a matrix invert).

 

Quick checking shows that it's working well; I'll of course let you know if I find any problems.

 

Edit: oh, the link above needs fixing, but I was able to get the file.

[SneaksieDave]

I noticed that the simple patch mesh has the option to remove the originating brush (entry #120 - I didn't want to just open it back up since it's not my entry, and maybe you are done with it). Can we have that ability for all types? Or, since the others don't include an intermediate dialog, could it be a global user preference? I find that I never need the brush after making a patch from it.

[greebo]

Can we have that ability for all types? Or, since the others don't include an intermediate dialog, could it be a global user preference? I find that I never need the brush after making a patch from it.

For what types do you mean exactly? You mean the end caps/inverted bevels?

 

(Besides, I never needed any brush to create a patch, therefore I never missed that option. I never quite understood why I'd have to create a brush first and then a patch out of it, if I can create it from nothing in the first place.)

[OrbWeaver]

(Besides, I never needed any brush to create a patch, therefore I never missed that option. I never quite understood why I'd have to create a brush first and then a patch out of it, if I can create it from nothing in the first place.)

 

Until I read this comment, I was under the impression that the only way to create a patch was from a brush. I just tested, and apparently you can create a simple patch mesh from nothing, which just creates a square patch at the origin.

[greebo]

Moreover, it creates a patch that fits the size and location of the last selected brush (doesn't have to be selected anymore). So it gets created where you are actually working (I think this area is called "workzone", but I'm not quite sure. At least it gets created in the orthoview where you are currently looking at.

[New Horizon]

Finally got the build process to work under windows. I'll be able to test more often now. Thanks for the tutorial on the wiki.

[SneaksieDave]

Just tried it. So if you really need a perfectly sized patch, you could draw the brush, delete it, and then create a patch out of nothingness. Interesting, I did not know that.