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Greg · 12-16-2007, 02:09 AM

A bit more precisely:

Mesh - The 3D model that defines the shape of an object. A mesh is defined by its vertices (in this useage, a vertex is a point space), wireframe (the lines that connect the points), and polygons or faces (the triangles that connect the points).

Texture - The same thing as a skin. The texture is an image that gets mapped onto the mesh and gives it its color. In The Sims 2, these are .bmp format pictures stored in the .package files. SimPE uses .png images for exporting and importing textures for some obscure reason that assuredly makes sense in some alternate universe.

A texture can have 2 or 3 parts:

Main texture - the color of the clothing with all the nuances and details.
Alpha - a black and white image that tells what areas the clothing covers. Black is no coverage, white is solid coverage, shades of gray are partially transparent.
Normal - also known as a bump map, shows where the shape is smooth or bumpy. Often used to make things appear to be raised or ribbed in clothing. Often omitted entirely. The normal causes the graphics card to calculate shadows but does not actually alter the shape of an object.

Skeleton - Also known as the bones, the skeleton is a three-dimensional stick figure that's tied to the mesh. The skeleton has the joints that move to adopt a pose, or by moving through a series of poses, an animation.

For example, here is a sim that I just installed this evening.

Christie Maas
Christie was created by Bunniewren; her clothing and silly name are my fault. Clothing mesh by BlooM.

Note that Christie's dress is very thin and that you can see a bit of her skin through it. That's because in the areas you can see through, the alpha in the dress texture is gray, not white. In the areas of her dress (and undies) that are opaque, the alpha is white.

The shapes of Christie's body and outfit are defined by the meshes. I used the plural becuase the mesh is a special outfit created by BlooM; it is an "alpha" mesh with separate meshes for the body, dress, and boots. (Called "alpha" because if you mess with the alpha layer of the clothing texture, you will see the shape of the separate body mesh through the holes.) Each one of those meshes has the full set of texture images associated with it.

This allowed me to have a transparent dress with Christie's nude body visible beneath it. (Well, nude except for her undies, which are mapped onto her nude body mesh.) Beneath her dress, nude body mesh is Warlokk's 34De36 mesh. It's that shape because BlooM included a mesh of that shape with his dress mesh. Christie also happens to have that same body shape assigned as her nude mesh but in reality any sim with any nude body shape could wear this dress and would have exactly the same body shape shown here.

Here we see Christie climbing stairs.

She is excuting the "climb stairs" animation because the game is moving the joints of her skeleton, and in turn, the skeleton is pushing the meshes that define the shape of her body, dress, and boots.

Was that at all clear?

12-16-2007, 02:09 AM	#3
Greg Da Guy Wut Owns Dis Joint Join Date: Mar 2007 Location: Texas Posts: 3,566	A bit more precisely: Mesh - The 3D model that defines the shape of an object. A mesh is defined by its vertices (in this useage, a vertex is a point space), wireframe (the lines that connect the points), and polygons or faces (the triangles that connect the points). Texture - The same thing as a skin. The texture is an image that gets mapped onto the mesh and gives it its color. In The Sims 2, these are .bmp format pictures stored in the .package files. SimPE uses .png images for exporting and importing textures for some obscure reason that assuredly makes sense in some alternate universe. A texture can have 2 or 3 parts: Main texture - the color of the clothing with all the nuances and details. Alpha - a black and white image that tells what areas the clothing covers. Black is no coverage, white is solid coverage, shades of gray are partially transparent. Normal - also known as a bump map, shows where the shape is smooth or bumpy. Often used to make things appear to be raised or ribbed in clothing. Often omitted entirely. The normal causes the graphics card to calculate shadows but does not actually alter the shape of an object. Skeleton - Also known as the bones, the skeleton is a three-dimensional stick figure that's tied to the mesh. The skeleton has the joints that move to adopt a pose, or by moving through a series of poses, an animation. For example, here is a sim that I just installed this evening. Christie Maas Christie was created by Bunniewren; her clothing and silly name are my fault. Clothing mesh by BlooM. Note that Christie's dress is very thin and that you can see a bit of her skin through it. That's because in the areas you can see through, the alpha in the dress texture is gray, not white. In the areas of her dress (and undies) that are opaque, the alpha is white. The shapes of Christie's body and outfit are defined by the meshes. I used the plural becuase the mesh is a special outfit created by BlooM; it is an "alpha" mesh with separate meshes for the body, dress, and boots. (Called "alpha" because if you mess with the alpha layer of the clothing texture, you will see the shape of the separate body mesh through the holes.) Each one of those meshes has the full set of texture images associated with it. This allowed me to have a transparent dress with Christie's nude body visible beneath it. (Well, nude except for her undies, which are mapped onto her nude body mesh.) Beneath her dress, nude body mesh is Warlokk's 34De36 mesh. It's that shape because BlooM included a mesh of that shape with his dress mesh. Christie also happens to have that same body shape assigned as her nude mesh but in reality any sim with any nude body shape could wear this dress and would have exactly the same body shape shown here. Here we see Christie climbing stairs. She is excuting the "climb stairs" animation because the game is moving the joints of her skeleton, and in turn, the skeleton is pushing the meshes that define the shape of her body, dress, and boots. Was that at all clear? __________________ Who are all these people and what do they know? Last edited by Greg : 12-16-2007 at 02:36 PM.