# Tag Info

## Hot answers tagged model

16

Smooth in this case just makes the surface normals at vertices point the same way, when interpolated it looks smooth. Meshsmooth would add vertices. 1) how is the smoothing possible without increasing the detailing of the mesh geometry? Human eyes cant actually see curvature except on the edges of objects. All they can do is approximate the smoothness and ...

5

The magic is that the mesh is attached to the skeleton. In it's simplest form, this is done by assigning each vertex to a bone. When a vertex is assigned to a bone, that means that it will always keep the same position relative to that bone's position, and orientation (normal, tangent, bitangent aka the bone's local X,Y,Z axis) as the bone moves as ...

3

Google said how in 2012, avoiding explaining too many details The never-ending quest for the perfect map ...new imagery rendering techniques and computer vision that let us automatically create 3D cityscapes, complete with buildings, terrain and even landscaping, from 45-degree aerial imagery and here it's a video of the feature. So we know that "...

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Don't copy around huge chunks of data if you don't have to. I would delay collecting and building the final forest mesh for as long as possible. However when you have multiple of the same mesh that just needs to be translated and rotated a bit you can use instancing. Which lets you draw thousands of copies of a tree with a single draw call. The most ...

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You should look into Medial Axis Transform or Straight Skeletons. They are often used to generate the information you need to bevel things properly. They give you a distance from the bounds of your object at any point in space, which allows you to generate bevels correctly. They are difficult to calculate, though. You may also want to look into this paper ...

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It's easy to work out if you consider not that case but the angle at v3 (if the "cube" were continued past v3). By the time you get to v3, the angle is simply the desired bend angle. (That's not quite right, though: because you've got alpha on the decreasing side, it's 90 degrees minus the desired angle.) You have to split that angle equally among all the ...

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A fragment shader receives the gl_FrontFacing system-defined input value. It will be false if the fragment was generated from a back-facing triangle, and true otherwise. So you can use that in your shader to determine how to generate a color value.

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Volumetric Modeling usually refers to using a regular 3D grid of voxels, analogous to 2D pixels, to define properties of an object at points or small regions of space. While more complex data might be stored at each voxel, often each contains a simple vector of values which can be interpreted directly as density or material properties for analysis and ...

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It sounds like you want to know how to ray trace a bilinear surface patch. A quick search turned up this page by Ramsey, Potter & Hansen, which includes a paper and, probably better still, source code! However, if you just want a "cheap and cheerful" hack approach, you could try replacing the quad with 4 triangles. That is, by a new vertex at the '...

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Why are wireframes used? Games don't really use wireframes much, but they might be useful for HUD items etc. Asset creators, designers and engineers use wireframes to see whats inside objects. TO clarify the edged between elements or to preview unimportant aspects. Image 1: Different 3D views (click to zoom) Engineers and Architects also may have very ...

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Regarding wireframes as an edge list. Wireframe models are used in engineering and CAD they provide several benefits. The Wikipedia page you linked has some benefits, this AutoCAD page has some more. Wireframe are used less in games and movies since they are generally more concerned about the visuals and wireframes are more concerned about design (form over ...

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AssImp library may be a good choice for you, assuming you are using C++ ?. It supports a decent number of model formats.

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I have done 3D graphics in c# with Managed DirectX. Nowadays people uses SharpDX and SlimDX instead. I have heard about XNA is easier for doing simple 3D games. You can also use OpenGl since there are several bindings for C#. Some people find OpenGl simpler to understand than DirectX, and is cross platform. Unity uses C# as scripting language, the Unity ...

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If we sidestep your typo (the last term has one absolute too much), both formulations are correct. They just express different things. The $k$ in Hooke's law is for a particular spring. $k_s$ is the siffness for a paricular material. Now in the linear portion there is a direct relationship betwen these the material stffness is directly propotional to the ...

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The accessor (model.accessors[accessor_index]) has its own byteOffset and count values that you need to account for here. The input and output accessors are allowed to share a bufferView, and your output is showing a dump of the same entire bufferView twice. The first five values in that dump are the input accessor with the times (in seconds, since the ...

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I'm not familiar with the exact nuances of the STL format, but here are some answers on general computer graphics principles: In the source file, the Vertex Normals are specified and in the destination, the face normal of the triangles are present which are different than the normals one would get by (a-b) x (a-c), where a, b, c are the vertex coordinates ...

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Textures are applied to the faces of a mesh, so textures cannot be anywhere there isn't a face for it to appear on. "Adding more length" to a mesh pretty much implies moving some of the vertices. I don't think you're going to get around that. Now if you are assembling a game world, it's quite common to have modular mesh pieces that can be aligned ...

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The Phong lighting model computes the specular response as the dot product between the mirror reflection direction and the viewing direction, raised to a power. For example, if $\vec{V}$ is the viewing direction, $\vec{L}$ the incoming light direction and $\vec{R}$ the perfect specular reflection direction for $\vec{L}$, then the specular response is $\text{... 1 You can render with a raymarcher and using distance fields. For the hat you would define the center and radius of the cylinder, and would draw any march which falls within such circle, no matter what "height" you are in, it will be infinite. You can also add a restriction, like y > 0 to put a beginning to your hat. 1 I think getting the real data with high precision is not easy without some API. The first idea would be just to manually use some color based selection tool that you can tell to select all areas in the screenshots according to the lookup table. But that would not result in some 3D data, but only segmented images where you can annotate the values. Another ... 1 I can see two ways of doing "smoothing". The first one is smoothing what's mostly related to the appearance (in your case the normals). The other way is smoothing the geometry itself. In the first case you usually update the normals based on the neighbours. Say$\mathcal{M}$is a mesh,$T$is a triangle in$T$and$n(T)$is the normal at$T\$. One ...

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