Questions tagged [c++]
The c++ tag has no usage guidance.
173
questions
1
vote
1answer
24 views
Environment map importance sampling (beginner)
beginner here.
I am implementing importance sampling for environment maps in Scotty3D, a CMU CS project (but I am not a student).
The task can be found here
I have a problem with the sample's pdf, it ...
0
votes
0answers
13 views
Data from staging Texture2D incorrect (DirectX 11)
I'm trying to implement 3D picking in my engine. To do this I am rendering objects with different colours and getting the pixel at certain mouse position and extracting the colour value from a special ...
-1
votes
0answers
15 views
OpenGL: Error glVertexAttribDivisor not found
The function glVertexAttribDivisor when used with CMake - it just throws the following error during compilation, which means that function is not imported.
...
0
votes
1answer
54 views
Half-Edge Data Structure with holes
I am trying to implement next/prev of edges in half-edge data structure. But I ran into this question. If there are two holes with a common vertex, will the closed loop of the edges run as in the ...
0
votes
1answer
48 views
My OpenGL program is not drawing filled polygons
I'm trying to learn OpenGL in c++ (I used it in Java) but I have a problem, I make a triangle, but it doesn't draw on GL_FILL and in GL_LINE it just draw a line, I can't find my mistake, I guess my ...
0
votes
0answers
32 views
Weird PIX behavior with DXC
Recently I've switched from FXC to DXC to compile shader model 6.0. It compiles well without errors (and runs well) but I can't debug shaders because on my netbook PIX says "failed to load PDB ...
1
vote
1answer
148 views
Understanding fragment shader coordinate system
I'm trying to create an infinitely panable grid using fragment shaders (C++/OpenGL/GLSL), and I'm having a bit of difficulty understanding the coordinate system.
This is my fragment shader code, ...
0
votes
0answers
14 views
How to read .gltx files using jansson JSON C library?
I am currently writing a program to parse the .gltf file using the jansson C library for reading JSON files. I want to show how that library is effective in reading .gltf files so that apps can use ...
0
votes
0answers
38 views
Under what conditions does a mesh operation cause the mesh become non-manifold and how to avoid it?
I'm implementing some mesh operations (e.g. edge collapse, edge split, edge flip etc) and need to ensure applying such operations does not cause the mesh to become non-manifold. However, I'm not sure ...
0
votes
1answer
47 views
Buggy behavior when applying specular reflection
I'm very new to computer graphics and trying to implement a raytracer based on the book Computer Graphics from Scratch. When I tried to add specular reflection, I don't get the output that look like ...
0
votes
1answer
49 views
(Ray tracing) Trouble converting to screen coordinates, objects being stretched
I followed along with Ray Tracing in One Weekend and managed to get the final output but I wanted to understand more about creating a camera and "painting" the screen since he didn't go over ...
0
votes
0answers
65 views
Using multiple textures in a shader
Background:
I am extracting the textures for a model with Assimp and sampling those textures in the fragment shader. I have multiple uniform sampler2D textureN ...
0
votes
0answers
35 views
Path tracing: how to ensure the new direction vector is a valid direction vector with respect to a BSDF?
Given the BSDF function and the Normal vector of the intersection point in world space, how can I generate a new direction vector ...
0
votes
1answer
41 views
How to link Intel Open Image Denoise in Qt Creator and use it to denoise noisy Monte Carlo path tracing renderings?
I've been trying to link my the Intel Open Image Denoise libraries for about a week and still have no luck as of now. This could partly be because I am also novice in C++ stuff. So I need some help in ...
0
votes
1answer
39 views
Spline interpolation library in cpp
Have been searching a lot for a good spline interpolation library in cpp, came across one, which is the famous Eigen library , having the unsupported counterpart for spline fitting.<Here>.
I ...
0
votes
1answer
55 views
Vulkan clear color is wrong
I am following https://vulkan-tutorial.com/Introduction to get myself familiar with the Vulkan API. I have gotten to the point where my application is able to draw a triangle. But for some reason the ...
0
votes
0answers
14 views
how to convert halfedge datastructure to work with GTS
I want to import an object with extension ".obj" as halfedge data structure. and simplify it using GTS (GNU Triangulated Surface Library. )
How to convert halfedge data structure to ...
0
votes
0answers
16 views
how to use half-edge data structure with gts gnu
There is any way to use GTS(GNU Triangulated Surface Library) with Half-edge or Combinatorial maps data structures ?
I want to use GTS simplification with the above mentioned data structures
I ...
0
votes
1answer
60 views
Efficiently transferring only needed parts of the vertex data to the GPU (C++/OpenGL)
I have a situation, where I have an array of vertices on the CPU side, for which, besides rendering-relevant data, like their position, I have a lot of other data at each vertex. All vertex data is ...
0
votes
1answer
85 views
Render fragments with uvs outside (0,1) range as transparent
I'm rendering an image onto a mesh. And I need to render fragments with uv coordinates that fall outside (0,1) range with full transparency. In the code below I'm specifying a border color with zero ...
2
votes
0answers
54 views
Atmospheric scattering band/seperation artifact
I am currently experimenting with some atmospheric scattering in glsl in my OpenGL engine.
I am experiencing a strange phenomena where a strange band / separation artifact appears along the middle of ...
0
votes
0answers
43 views
How to deallocate memory for vertex buffer objects
I have a class that handles loading buffers for a mesh:
...
0
votes
1answer
207 views
Drawing a square using glDrawArrays with GL_TRIANGLES
I used a version of the following code to draw a triangle using glDrawArrays with GL_TRIANGLES, per Anton Gerdelan's very nice tutorial here:
Hello Triangle !
It draws a nice triangle.
I have modified ...
0
votes
0answers
26 views
What do you do when the root skeleton is not defined in a gltf file?
Cross posting from stack overflow:
Reading the source code of tinygltf I see this:
...
0
votes
0answers
54 views
Different OpenGL behaviour on Windows and Ubuntu
While porting this project with slightly modified code to Linux I ran into some weird behaviour.
On Windows it runs just fine (https://youtu.be/xH6Dc6xOuow).
But on Ubuntu it shows some weird ...
1
vote
1answer
21 views
Why are these 2 buffers joint while extracting glTF information?
I am using tinyGLTF to parse gltf files and then render them in my program.
I am currently during the third example in this page.
In particular I am trying to extract the 2 animation buffers:
My code:...
1
vote
1answer
68 views
Max number of elements in a vertex attribute
I want to load a vertex buffer with vertices of struct Vertex:
...
0
votes
1answer
35 views
In place sorting of a half edge DS?
Cross posting from SO because I didn;t know where to put this question.
I have an implementation of the half edge and I am trying to sort the edges such that edge n+1 is the pair of edge n.
Setup
I ...
1
vote
1answer
49 views
draw on cubemap with help of geometry shader each triangle covers each cubemap face (why??)
I want to do some complicated stuff but have problems with my geometry shader / FBO bindings.
To hold it as easy as possible I reduced the code to a minimum. If this works, I could continue the hard ...
2
votes
2answers
141 views
Using array of textures in DX12
I managed to create code, working correctly as Texture2DArray in hlsl by using single ID3D12Resource and binding it as D3D12_SRV_DIMENSION_TEXTURE2DARRAY with constant array size.
...
2
votes
0answers
46 views
Global root signature crash
I have a problem with RTPSO creation. Using local root signatures for each of rgs (ray generation shader), chs (closest hit), miss is working correctly. However, for performance sake, I want to use ...
2
votes
0answers
37 views
multiple Quaternion slerp inverse to calculate relative coordinates
I am creating a 3D spherical curved display (only a part of a sphere). The camera usually is inside of this sphere. This display has texture coordinates. The image below shows the display with its ...
1
vote
1answer
92 views
Raytracer help - Background color writing over some colors?
I'm implementing Peter Shirley's "Raytracer in a Weekend: The next week" and I'm having some trouble with rendering a scene with a light. I'm not sure if the issue is the background color or ...
0
votes
1answer
49 views
Hit group - export already defined
I am getting this error when creating RTPSO with multiple hit groups:
...
0
votes
0answers
143 views
How to use RWStructuredBuffer
Edit: I managed to get code compiling, but it doesn't work, so I changed question a little bit.
Below code is working fine as read buffer, but I cannot make it to work as read-write buffer (...
0
votes
1answer
43 views
Paint pixels on the image around the cursor for painting application
I'm trying to create a simple painting application. And I was wondering about an efficient way to draw pixels on the screen.
I have a pixel struct:
...
0
votes
2answers
202 views
Get normalized device coordinate of an image pixel
I have an image rendered to the screen, and based on the normalized device coordinates of the cursor I would like to pick the pixel of the image under the cursor.
Say the image has four channels, I ...
1
vote
2answers
113 views
Why negate z when constructing projection matrix OpenGL
I constructed an orthographic projection matrix from this article on scratchpixel.com:
...
2
votes
1answer
134 views
Dynamic Ray-Triangle Intersection
I am working on a small simulation software which has a 3D Renderer that is using OpenGL. I render objects to the screen as triangle meshes. To be able to select the triangles on the screen, I have ...
1
vote
1answer
87 views
How do you loop through the contents of a buffer in DX11?
Okay, so I'm currently using the IAGetVertexBuffers() method and I'd like to loop through some of the returned buffers to verify the contents.
However, I'm kind of new to DirectX and C++ in general. I ...
3
votes
1answer
396 views
How to unproject cursor with orthographic projection
With perspective projection we can unproject screen space coordinates of the cursor to the near and far plane of the frustum and calculate the direction of the ray through the cursor.
...
1
vote
0answers
47 views
What modern C++ Unit Testing Framework do you use for highly parallel image, 3D and higher dimensional matrix processing workloads? [closed]
Most of the existing open-source libraries such as OpenCV, Tensorflow, and Pytorch use Google Test. I would like to know about strong alternative testing frameworks that thrive under a similar ...
3
votes
1answer
236 views
Shader that transforms a mercator projection to equirectangular?
I am new in the OpenGL - GLSL and trying to make a shader that taking a mercator projection texture as a source and converting it to an equirectangular projection texture.
Sample input: (1024x1024)
...
1
vote
0answers
60 views
What is the projection matrix of reverse (Byzantine) perspective?
I would like to construct a projection matrix for reverse perspective.
I'm using OpenGL and tried to modify concepts from this excelent tutorial.
I came up with:
$$
\begin{bmatrix}
2\frac{(near-M)}{...
1
vote
1answer
40 views
Do we have OpenGL shaders write out the intermediate *.o-esque file on first compile so that we can skip compiling them in run-time every single time?
Shaders get compiled during runtime every single time an app starts. I understand the reasoning for this is that there are so many GPU architectures out there that it does not make sense to ship pre-...
1
vote
1answer
117 views
Passing mat4 array to GLSL succeeding but producing GL_INVALID_OPERATION
I'm currently passing an array of bone positions to GLSL for a skeletal animation shader; the positions are passing successfully but producing a GL_INVALID_OPERATION error.
I'm passing the matrices ...
2
votes
1answer
70 views
Off by one error when creating face indices
I seem to have an off by one error when creating the indices for the faces of a sphere and I can't understand where.
The exact problem is that when I try to calculate the normals of each face a dark ...
0
votes
0answers
107 views
Queue from a family queue that supports presentation doesn't work [Vulkan]
I'm following this tutorial on Vulkan and I tried to see if it actually worked with different queues for drawing and presenting the image of the triangle. My GPU supports presentation with every queue ...
0
votes
1answer
264 views
Feeding acceleration structure to the GPU then raytracing it in a compute shader?
I want to use Vulkan's rasterization to solve for the visibility problem, but once that is done I want to do shading, reflection and transmission through a raytracer which also runs on the GPU. With a ...
1
vote
0answers
69 views
How do I produce a metallic surface in ray tracing?
I can't manage to produce a metallic looking sphere despite trying many things. I have the basics working, i.e shadows, refraction etc. but I'm not sure what combination of these will allow me to ...
