i try to implement voxel cone tracing in my game engine.
I have read many publications about this, but some crucial portions are still not clear to me.
At first step i try to emplement the easiest "poor mans" method
a. my test scene "Sponza Atrium" is voxelized completetly in a static voxel grid 128^3 ( structured buffer contains albedo)
b. i dont care about "conservative rasterization" and dont use any sparse voxel access structure
c. every voxel does have the same color for every side ( top, bottom, front .. )
d. one directional light injects light to the voxels ( another stuctured buffer )
I will try to say what i think is correct ( please correct me )
GI lighting a given vertecie in a ideal method
A. we would shoot many ( e.g. 1000 ) rays in the half hemisphere which is oriented according to the normal of that vertecie
B. we would take into account every occluder ( which is very much work load) and sample the color from the hit point.
C. according to the angle between ray and the vertecie normal we would weigth ( cosin ) the color and sum up all samples and devide by the count of rays
Voxel GI lighting
In priciple we want to do the same thing with our voxel structure.
Even if we would know where the correct hit points of the vertecie are we would have the task to calculate the weighted sum of many voxels.
Saving time for weighted summing up of colors of each voxel
To save the time for weighted summing up of colors of each voxel we build bricks or clusters.
Every 8 neigbour voxels make a "cluster voxel" of level 1, ( this is done recursively for many levels ).
The color of a side of a "cluster voxel" is the average of the colors of the four containing voxels sides with the same orientation.
After having done this we can sample the far away parts just by sampling the coresponding "cluster voxel with the coresponding level" and get the summed up color.
Actually this process is done be mip mapping a texture that contains the colors of the voxels which places the color of the neighbouring voxels also near by in the texture.
Cone tracing, howto ??
Here my understanding is confus ?? How is the voxel structure efficiently traced.
I simply cannot understand how the occlusion problem is fastly solved so that we know which single voxel or "cluster voxel" of which level we have to sample.
Supposed, i am in a dark room that is filled with many boxes of different kind of sizes an i have a pocket lamp e.g. with a pyramid formed light cone
- i would see some single voxels near or far
- i would also see many different kind of boxes "clustered voxels" of different sizes which are partly occluded
How do i make a weighted sum of this ligting area ??
e.g. if i want to sample a "clustered voxel level 4" i have to take into account how much per cent of the area of this "clustered voxel" is occluded.
Please be patient with me, i really try to understand but maybe i need some more explanation than others
best regards evelyn
By Michael Santer
We're currently two programmers and a game designer working on a turn-based tactics fantasy board game. For reference you can search for images of "Tactics Arena Online", a fairly dated game that used to have a lot of depth and complexity.
Our goal is to use the same combat concepts, but giving it a much needed modern touch as well as a whole new set of heroes to choose from with additional abilities. The game is a mix of isometric and 3D and we plan to release the game on Steam and hopefully Android & iOS as well.
We are looking for someone to work with us pro-bono (just like we're doing) as a 3D character artist. The skills needed are creativity, a hard working attitude and an ability to make minor animations (things like idle, walk, block and very rudimentary attack animations). A perk to have would be the ability to make some VFX. If the game makes it on steam and money starts coming in, you'd obviously be compensated for your hard work, but as it stands this is a hobby project to garnish your portfolio.
A bit more about the game:
This game will be an online multiplayer game where each user gets to pick up to 10 characters to place on his half of the board (this would be done before even entering matchmaking. Think runes in League of Legends for example). The user can place his 10 units of choice anywhere he likes on his half board. Some units can be used more than once. So if you want 4 knights and 2 mages or even if you want 10 clerics, you can do as you please. You can then save your setups for future use. The goal of the game is to wipe out the enemy team.
Each character or Hero (except premium and abyss characters) start with 1 ability and they can ascend (either by playing a certain amount of matches with the character or by forcing the ascension with real money) to gain a new ability or passive. Acquiring a new character can be done by using in-game currency that you earn from playing matches or using real money with the exception of Abyss characters which can only be acquired by winning certain rare matches. The goal is to offer a freemium game with lots of customizable elements while making sure that no user can "buy power" with real money. We want everything that a paying user can get to be available to non-paying users who play the game a lot.
Ultimately we want this to become a competitive game that people can enjoy and really get invested in. Each character is designed with options for counterplay in mind and synergy with other heroes.
We sincerely believe in what this game can become and we home to find someone just as passionate as we are to get involved in this project!
By Marinka Brussel
Imagine a game where the characters are not defined by body regions, but rather, each body region consists of thousands of components, which would kind of replicate the real world where we consist of molecules, atoms - that would open up many, many new possibilities for creative gameplay. Can this be done on any scale with today's technology, or would the games simply require too powerful of a computer to even be playable? Are there any theoretical limits to this? Thanks
Hi guys, when I do picking followed by ray-plane intersection the results are all wrong. I am pretty sure my ray-plane intersection is correct so I'll just show the picking part. Please take a look:
// get projection_matrix DirectX::XMFLOAT4X4 mat; DirectX::XMStoreFloat4x4(&mat, projection_matrix); float2 v; v.x = (((2.0f * (float)mouse_x) / (float)screen_width) - 1.0f) / mat._11; v.y = -(((2.0f * (float)mouse_y) / (float)screen_height) - 1.0f) / mat._22; // get inverse of view_matrix DirectX::XMMATRIX inv_view = DirectX::XMMatrixInverse(nullptr, view_matrix); DirectX::XMStoreFloat4x4(&mat, inv_view); // create ray origin (camera position) float3 ray_origin; ray_origin.x = mat._41; ray_origin.y = mat._42; ray_origin.z = mat._43; // create ray direction float3 ray_dir; ray_dir.x = v.x * mat._11 + v.y * mat._21 + mat._31; ray_dir.y = v.x * mat._12 + v.y * mat._22 + mat._32; ray_dir.z = v.x * mat._13 + v.y * mat._23 + mat._33;
That should give me a ray origin and direction in world space but when I do the ray-plane intersection the results are all wrong.
If I click on the bottom half of the screen ray_dir.z becomes negative (more so as I click lower). I don't understand how that can be, shouldn't it always be pointing down the z-axis ?
I had this working in the past but I can't find my old code
Please help. Thank you.