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1
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1answer
39 views

Opengl Quad Tessellation Control Shader

I have the generic tessellation evaluation shader for triangles but I need to make it work for quads. Is there any chance someone could explain what is happening here and point me in the right ...
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0answers
56 views

Tessellation shader pass-through : Nothing displayed

I am trying to set a pass-through tessellation shader and then build on top of that while learning. From what I found/read I need to do in the TE shader everything that was done in the vertex shader ...
5
votes
1answer
612 views

Unity3D - How to tessellate 2D sprites?

I use dynamic vertex lighting on 2D sprites. On larger sprites the lighting is uglier than on smaller ones. This is because every sprite is just a quad of two triangles. Not enough vertices there for ...
0
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0answers
50 views

Small detail displacement

Hi I am new here so sorry if the question is wrong somehow. I've implemented displacement with tessellation. I tessellate my mesh in the Tessellation Control Shader and then in the Tessellation ...
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vote
3answers
119 views

Technique suggestion to render corroded pipes in 3D

We currently have a lot of data relating to cracks/corrosion/deformations in metal pipes which at present, can be viewed in a crude flat/2D application which makes the metal anomalies hard to spot. ...
1
vote
1answer
170 views

Manually writing a dx11 tessellation shader

I am looking for resources on what are the steps of manually implementing tessellation (I happen to be using Unity CG, but any help is appreciated). Today it seems that it is all the rage to hide ...
7
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1answer
494 views

Tessellation vs Geometry Shader

Correct me if I'm wrong, but both the Geometry Shader and the Tessellation Shader jobs are to generate vertices in the Graphic Pipeline. What I would like to know is how they are different and when ...
0
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0answers
73 views

Collision at incorrect height between boxes and btHeightfieldTerrainShape

I'm using btHeightfieldTerrainShape from BulletPhysics for collision between fired boxes and a terrain. But such boxes seem to collides at higher positions above the terrain as the following picture. ...
4
votes
1answer
213 views

Calculating normals after displacement mapping

I'm using C++, DX11 and tessellation. After tessellating a triangle I apply displacement mapping to the new vertices. But they still have the original triangle's normal so the lighting calculation ...
2
votes
1answer
126 views

Do the predefined HLSL semantics carry any meaning?

I'd say there are 3 kinds of HLSL semantics: SV_* group - these are "system value" semantics which DO carry special meanings (e.g. assign special input/output data to/from shader stages) predefined ...
0
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1answer
177 views

Easiest way to smoothen coarse mesh with HLSL?

I've browsed through a couple of presentations and papers about DX11 tessellation and they all say that one of the most common usages of tessellation is to take a coarse (low poly) mesh, smoothen it ...
5
votes
1answer
307 views

What is the role of tessellation in terrain?

I'm relatively new to graphically programming and I've been looking into ways to render larger heightened terrain. I keep seeing comments directing me to disregard things such as geometry clipmaps, in ...
1
vote
1answer
270 views

Infinite / Treadmilling Hexagonal Grid

So, I can happily render an infinite square grid by moving said grid whenever the camera moves out of a grid square, auto diff = (cameraTranslation - gridTranslation); bool moveGrid = false; if ...
2
votes
1answer
151 views

Tessellation cracks

i'm trying to a mesh tessellate with dx11 with the tessellation factor calculated by the size of the triangle and the distance to the screen. I do the same operation on the 3 edges of the triangle, ...
0
votes
1answer
149 views

Linking error at tessellation shaders in GLSL

I'm testing the triangle tessellation from the link http://prideout.net/blog/?p=48#shaders . All the shader are compiled correctly, but when I try to link the program using the command: ...
3
votes
1answer
171 views

How is displacement tessellation done?

I'm curious because I was thinking that displacement mapping is done in the shader file only inside the domain shader. Am I correct or is it both implemented in the rendering section of the mesh and ...
1
vote
0answers
52 views

Approximating Subdivision Surfaces with Gregory Patches for Hardware Tessellation

I'm trying to implement the approach (http://research.microsoft.com/en-us/um/people/cloop/sga09.pdf). Unfortunately I'm not quite clear regarding the formulas in chapter 3, I am hoping to get some ...
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4answers
2k views

What's the difference between displacement mapping and height mapping?

What's the difference between displacement mapping and height mapping and what is the connection to adaptive tessellation?
3
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2answers
238 views

Subdividing a polygon into boxes of varying size

I would like to be pointed to information / resources for creating algorithms like the one illustrated on this blog, which is a subdivision of a polygon (in my case a voronoi cell) into several boxes ...
0
votes
1answer
290 views

DirectX 11, using Tessellation & Geometry shader in a single pass

Before all, sorry for my poor english ! With DirectX 11, i'm trying to create a random map full with GPU. Using Hull shader stage, I'm managing LOD with tessellation. Using Domain shader stage, I'm ...
3
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2answers
472 views

How to subdivide a quad?

I'm working with OpenGL and I'm importing from a file coordinates for quads in the following format: 0.0 1.0 0.0 //normal vector 20.0 -5.0 20.0 10.0 10.0 //x y z u v 20.0 -5.0 -20.0 10.0 0.0 ...
1
vote
2answers
305 views

Building a tessellated texture

In games like Minecraft the textures such as grass when lined up side-by-side it looks like one big perfect texture. When I make a texture it's never even and you can see the different blocks. How do ...
5
votes
1answer
713 views

Tessellation Texture Coordinates

Firstly some info - I'm using DirectX 11 , C++ and I'm a fairly good programmer but new to tessellation and not a master graphics programmer. I'm currently implementing a tessellation system for a ...
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4answers
2k views

Generating triangles from a square grid

I have a 2D square grid of values representing terrain elevations, and I want to generate triangles from that grid to make a 3D view of the terrain. My first thought was to split each square ...
2
votes
0answers
352 views

Per fragment lighting with OpenGL 4.x tessellated model

I'm experienced with OpenGL 3+. I'm dabbling with tessellation shaders and have now got to a point where I have a nicely tessellated teapot/plane demo (quick look here) As can be seen from the ...
2
votes
3answers
430 views

Tessellating to a curve?

I'm creating a game engine, and I'm trying to define a 3D model format I want to use. I haven't come across a format that quite does what I want. My game engine assumes a shader model 5+ environment. ...
11
votes
2answers
2k views

What OpenGL version(s) to learn and/or use?

So, I'm new to OpenGL... I have general knowledge of game programming but little practical experience. I've been looking into various articles and books and trying to dive into OpenGL, but I've ...
0
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1answer
408 views

OpenGL Tessellation makes point

A little problem with my tessellation shader. I try to implement a simple tessellation shader but it only makes points. Here's my vertex shader : out vec4 ecPosition; out vec3 ecNormal; void ...
1
vote
1answer
321 views

What are the tessellation factors Direct3D11?

I don't quite understand the documentation but if I was to tessellate a mesh using 3 control points in Direct3D11 with the "tri" domain am I right in thinking that SV_TessFactor is how many times to ...
5
votes
1answer
383 views

Directx11 / Tessellation

What is so special about directx 11's dynamic tessellation? Can't it be implemented by hand, and just render geometry tessellated by your own code using older versions of directx? What are the ...
3
votes
2answers
612 views

Code to tessellate a general quadric

Does anyone know of a C/C++ library (or has some source code) that can generate and output (by which I don't mean render) a tessellation of a general quadric, i.e. a 3d surface defined by the matrix ...
20
votes
9answers
4k views

When mapping the surface of a sphere with tiles, how might you deal with polar distortion?

It's easy to deal with the way locations interact on a clean Cartesian grid. It's just vanilla math. And you can kind of ignore the geometry of the sphere's surface for a bunch of it if you want to ...
27
votes
3answers
9k views

How does hardware tessellation work?

I would just like someone to explain in relativly clear terms how hardware tessellation works considering it is the new buzzword with DX11. Thanks.