Weird Shadow After Combining Mesh Parts

[mocha0030]

I combined two body shape meshes at the waist. The problem I'm having is there is now a weird shadow below the breasts. I don't know how it happened or how to get rid of it. I read the tutorial All About Normals (http://hideki.modthesims2.com/showthread.php?t=225607&goto=newpost), which I think may be my issue, but I wasn't able to make sense of it.

Original mesh:

http://i600.photobucket.com/albums/tt82/mocha_0030/tutorials/bc1.jpg

My edit:

http://i600.photobucket.com/albums/tt82/mocha_0030/tutorials/bc2.jpg

In addition to combining the two meshes at the waist (the red line on my mesh above is a rough estimate of where I joined them), I also removed nipples from the breasts so they would look smooth on clothing recolors. I selected the nipple faces, and deleted them, which created a small hole. Then I selected the vertices around the holes and used "snap together" to close the holes. This left a slight point at the tip, so I selected the surrounding vertices and used "align normals" to smooth out the point. I also aligned the normals around the waist where I connected the meshes.

I have no idea what I did wrong to create that weird shadow, which doesn't appear at all in MilkShape. Please... :help:

[Ken Murikumo]

when an angle is too obtuse or acute (oooohhh, big words) the shadows get wonky. If you make a cone and align normals on the whole cone, it turns black at the tip for the same reason.

The breast angle in tandem with the ribs portion of the torso, where they meet, is too acute. Select all verts that run under and around the breasts and go to "vertex < unweld" this will separate every triangle into 3 verts, regardless of overlapping verts (this wont mess up any normals, uv or rigging). Then go to "select face" and grab the entire breast segment with no torso underneath the breasts. hit align normals and it will normalize just the breasts, and separate them from the mesh (they will look similar to a plate of armor... kinda). then do the same with the torso and no breast (you dont *have* to select the *whole* torso, just the parts under the breast). now you will be left with two funky looking plates. go to "select verts" and start aligning normals on individual, or multiple if you want, verts starting from the top portion of the breast "plate" wrapping around to the sides. you will notice that it will blend the plate into the rest of the mesh. keep doing this till you get toward the side-bottom of the breasts, and stop where you find appropriate. the torso will need some work, too. depending on how you did this, you may need to do the same to the inside of the breasts not just the outside.

in short aligning normals on large bodily structures isn't a good idea. careful "hand-painted" normals will always look better...

[mocha0030]

Although your solution was too complicated for my skill level, thank you for taking the time to respond, Ken. I didn't use your method, but you confirmed for me that the issue was with aligning the normals. I'm not 100% sure what I did wrong the first time around, but I started over from scratch. Instead of combining the meshes two rows of vertices below the breast (perhaps it was too close?), I combined it 3 rows below and it turned out perfectly. No wonky shadows! Thanks again. :)

[Ken Murikumo]

yup. the angle was too acute. by adding new rows you altered the angles between and lessened the strain causing the black shadows.

yeah, that was a novel, but in practice its not as complicated...