Polygons with three corners or vertices and three sides or edges which are line segments.

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1
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1answer
61 views

How to reproduce this triangle filling scanline effect using a shader?

I'm writing a renderer for an old DOS game were 3D polygons were rendered in software. I'd like to simulate, using a shader, the following material/effect, used for filling a triangle : The fist ...
3
votes
1answer
72 views

The better performance in occlusion culling, plane or quad?

In the above picture, when the left camera shows two small parts of the quad, all of that is rendered (it can be a very large quad). But in the right one only two small parts of it is rendered. ...
0
votes
1answer
47 views

How to rotate a triangle towards the point in Qt?

I have an issue with items rotating. I have a point and a triangle which needs to be rotated with its apex point towards the taregt point. The right side of the picture represents how it is should to ...
0
votes
0answers
29 views

Triangle mesh - curvature

I have a triangle mesh with normals. What algorithm is considered to be "standard" with best possible quality for triangle mesh curvature computation (mean and gauss). Something like for normal ...
3
votes
2answers
99 views

Algorithm for triangle picking?

So i found out that i need a triangle picking algorithm, i need to see if my mouse is over the triangle. I've heard what color picking is, but it would pretty much just drop the performance twice ...
2
votes
1answer
162 views

Calculate the slope of a 3D triangle?

I have lots of triangles in 3D space. How do I determine the slope/angle of these triangles with respect to a fixed ground plane? I need pseudo code examples at the very least. Thanks! [edit] Based ...
0
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0answers
28 views

Strange offset when accessing pixels from an SDL surface

I am using a routine to map a triangle from one surface to another. The problem is that the function below chooses the correct pixel to draw on the destination surface, but the pixel selected from the ...
0
votes
1answer
104 views

Should a mesh consist of triangles or quads?

Currently I am a bit puzzled. I am writing my master thesis about procedural mesh and texture generation and for that I am writing a Blender Add-On to generate low poly planets with physical ...
2
votes
1answer
225 views

Generating mesh along path

I'm currently trying to generate a path along an array of points(Vector3) This is the result i'm currently getting The dark gray points are the given path The red points are the generated verticies ...
0
votes
0answers
29 views

How to calculate per vertex normals? (OpenGL) [duplicate]

I am really confused and quite much thinking about how to do that? Cross product and then, normalizing is not working for me. Or perhaps, I take them all wrong. Well, please explain me that while ...
1
vote
1answer
99 views

Does triangle-plane clipping in 3D always produce a triangle?

When you clip a triangle against a plane, will you always get a triangle out? Are there perhaps cases where you don't get a triangle out of clipping it against a plane?
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votes
1answer
92 views

Libgdx Drawing a triangle cannot resolve method “render ”

I am looking to draw a triangle. I found a lot of code such as : https://github.com/libgdx/libgdx/wiki/My-First-Triangle-%28Example%29 The code I found are old I think; if I use ...
2
votes
1answer
106 views

Make a triangular mesh from of a map defined by points that follow the coast lines

I have a set of points which follow the coast lines of a world map. I would like to somehow triangulate so that I can render the continents filled in. The points seam to be in order so that if you ...
2
votes
1answer
78 views

Good way to support multiple types of triangles? (C# XNA)

[this question is somewhat long. here's my question in a nutshell] I want to use multiple types of Vertex data types for my triangle, interchangeably. So if I have a generic type T private void ...
0
votes
1answer
412 views

Discarding triangles in Unity

I have about 2+ years of experience in computer gaming development and I just started writing my own shaders to help me utilize performance. I have this problem that I'm trying to work around but ...
1
vote
1answer
618 views

Triangle-Triangle Intersection Code

Does anyone have experience implementing this triangle-triangle intersection code that I found online? I don't understand it. I made a post on Stack Overflow about this and got the advice that: ...
3
votes
1answer
567 views

Fastest way to find closest triangle of mesh from specified point

I have two triangle meshes (let me call them A and B). The meshes may be really big (10.000 - 100.000 polygons). I want to find for every point in A the closest triangle from mesh B. Is there fast ...
1
vote
1answer
646 views

Triangles go missing as Z changes

I'm rendering a height map using shader-based OpenGL (3.3 to be precise). The height map data is from a grayscale bitmap (2D array of bytes). The dimension of the bitmap is 256 x 256. With this data, ...
0
votes
1answer
339 views

OpenGL: I only see one square instead of a cube / giving information to vertex shader

I am new to OpenGL and tried to follow this tutorial. I use C# and OpenTK. So I translate the C++ Code from the Tutorial: My C#-Code: /* Hintergrundfarbe */ ...
0
votes
1answer
96 views

Create dynamic cities of perspective angle x with least amount of tiles

I found you can create unique building sizes with perspective with six tiles using parallel projection, whose angles are always 45 degrees... this allows you to connect to the next tile without issue: ...
-1
votes
1answer
306 views

Why does this code to render a triangle in SlimDX only show a black screen?

Here is the code: var elements = new VertexElement[] { new VertexElement(0,0,DeclarationType.Float3,DeclarationMethod.Default, ...
3
votes
1answer
157 views

Generate 2D Triangular Mesh from Vertices on a Map

Given a map of vertices {(x1,y1), (x2,y2), ... (xn,yn)}, how can I generate a 2D triangular mesh covering all vertices, and where the area of all triangles completely covers the map? The triangular ...
1
vote
2answers
326 views

OpenGL drawing, breaking down triangles

if I want to use no textures in a game (i.e png's), would I just break down my drawing into triangles and combine them the way I want? I found this in Google Images.
1
vote
1answer
238 views

Given face normal and vertices of a triangle, how to find the acyclic order of vertices?

I'm in the process of constructing a custom 3D triangle mesh. I found the vertices of the triangle in the 3D space and it's face normal. How do I find the acyclic order of vertices? If I draw the ...
0
votes
2answers
187 views

How to draw non-triangulated mesh?

I am working with DirectX (C#/C++). I am wondering is it possible to do not triangulate meshes and what the difference between cases (in loading and rendering code)? If so, how to do this? I know ...
6
votes
2answers
1k views

Triangle-triangle continuous collision detection

I am making a 3D game engine and I use continuous collision detection. I am using Sphere-Trees to cull primitive collision checks to a minimum. However, I'd like to perform continuous ...
3
votes
1answer
336 views

Directional, Triangular Collision Detection in Pygame [duplicate]

I am trying to create a game in Pygame, with Python 3, and am trying to figure out an algorithm that will tell me which direction a rectangle is colliding with a rectangle, so that I can push it back ...
2
votes
1answer
487 views

How does the Direct3D 9 rasterizer determine triangle coverage?

I'm working on a software rasterizer to use in my project. I have implemented one that works well, however, often my rasterizer under or over estimates triangle coverage. I need perfect emulation of ...
2
votes
2answers
296 views

Angle between two planes

I have two triangles in 3d space which share 1 edge and I would like to determine if the angle between their normal vectors is "uphill" or "downhill". In other words, if you set one flat, would the ...
4
votes
1answer
2k views

Quads Vs Triangles

I'm curious to know which is better for games? Quads or Triangles? Wouldn't quads be better for rendering performances and smoothing out tessellation?
1
vote
2answers
154 views

XNA Calculate two points of triangle with given Z

I want to calculate the two points of a 3D triangle that have a specified Z coordinate. I guess the way to do this would be to somehow create a plane which is perfectly flat with my given Z coordinate ...
2
votes
1answer
3k views

How do I find the circumcenter of a triangle in 3D?

I want to find the circumcenter of a triangle. Wolfram only shows how to find the circumcircle of a triangle in R2. How can I find the circumcenter of a triangle in R3?
2
votes
1answer
213 views

SAT test for Triangle - convex hull

I'm having real trouble resolving this issue with triangle-convex hull SAT test intersection. The problem is as follows: Misses are detected accurately enough: Clear miss I have not found a ...
1
vote
1answer
221 views

Efficient way to draw multiple separated quads

Let's assume I want to draw several separated (possibly textured) quads in Direct3D 9, each consisting of two triangles: How should I draw these for maximum performance, i.e. which of the following ...
3
votes
1answer
256 views

Moller Tri Tri intersection

I'm done implementing Moller's tri-tri intersection routine. It gives you the location of where each triangle edge intersects the line of intersection between the 2 triangle planes: Really you get ...
0
votes
4answers
302 views

Is there a game not using meshes for models? [closed]

Traditionally, models consist of lots of vertices connected by triangles. That forces the use of a high amount of vertices for detailed organic shapes or makes models kind of blocky. Even though ...
0
votes
1answer
134 views

XNA 4.0 thick triangle strip to fix aliasing issues upon rotation

My triangle strip based lines are disappearing intermittently when I rotate my camera around the X axis. I was advised that this is due to aliasing issues and that "At a certain angle when its edge ...
0
votes
1answer
237 views

How do I implement my old OpenGL-based gfx_render_triangle_list using DX11?

I am working at a game that has lots of procedural content. I had built a game engine using OpenGL that handles everything needed for creating a basic 2D game, sprites, primitives, blending, polygons ...
7
votes
2answers
4k views

Unity's “Stats” window displays bizzare number of triangles and vertices

In my Unity scene I have: 7-8 Barrels (with lids) each at about 2-400 triangles. 4 planes, each at at the very most 200 triangles camera, 3 lights, a FPS controller When I turn on the "Status" ...
4
votes
2answers
315 views

Optimizing models & improving performance

I've created a map editor for a game I've been developing. The maps (planets) are made using a form of meta ball editing. Basically, in the end the Marching Cubes algorithm is used to get my final ...
5
votes
1answer
1k views

How to draw a trapezoid in OpenGL?

The question seems easy, but you simply change vertex positions to match the corners of a trapezoid but it simply fails. I've tried scaling top and bottom edges like this : but when I apply my ...
2
votes
3answers
7k views

Mesh with quads to triangle mesh

I want to use Blender for making models yet realize some of the polygons are not triangles but contain quads or more (example: cylinder top and bottom). I could export the the mesh as a basic mesh ...
1
vote
2answers
203 views

Point[] and Tri not “could not be found”

Hi I'm trying to learn how to load a .obj file using OpenTK in windows Forms. I have seen a lot of examples out there, but I do see almost everyone uses List, and Point[]. Code example show these ...
1
vote
2answers
329 views

Texturize a shape of multiple triangles in 2D

This is an example of a shape consisting of multiple points, triangles and eventually a shape: Red Dots = Vector3 (X, Y, Z) or Vector2 (X, Y) If I have a Texture of a certain size, how do I ...
0
votes
1answer
692 views

Fast software color interpolating triangle rasterization technique

I'm implementing a software renderer with this rasterization method, however, I was wondering if there is a possibility to improve it, or if there exists an alternative technique that is much faster. ...
2
votes
1answer
430 views

Software rendering 3d triangles in the proper order

I'm implementing a basic 3d rendering engine in software (for education purposes, please don't mention to use an API). When I project a triangle from 3d to 2d coordinates, I draw the triangle. ...
2
votes
2answers
221 views

Drawing multiple triangles at once isn't working

I'm trying to draw multiple triangles at once to make up a "shape". I have a class that has an array of VertexPositionColor, an array of Indexes (rendered by this Triangulation class): ...
2
votes
3answers
442 views

Polygonal Triangulation - algorithm with O(n log n) complexity

I wish to triangulate a polygon I only have the outline of (p0, p1, p2 ... pn) like described in this question: polygon triangulation algorithm and this webpage: ...
12
votes
3answers
3k views

Why are triangle fans not supported in Direct3D 10 or later?

http://msdn.microsoft.com/en-us/library/windows/desktop/bb206271(v=vs.85).aspx Why? Are there inherent drawbacks to working with triangle fans?
7
votes
2answers
404 views

Must I worry about quad-based rendering in real world scenarios?

Most of the time in the first chapters of a random book about rasterization and rendering techniques, I find some phrases about a triangle-based rendering system and a quad-based one. I have never ...