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• ### Similar Content

• By fs1
I have been trying to see how the ID3DInclude, and how its methods Open and Close work.
I would like to add a custom path for the D3DCompile function to search for some of my includes.
I have not found any working example. Could someone point me on how to implement these functions? I would like D3DCompile to look at a custom C:\Folder path for some of the include files.
Thanks
• By stale
I'm continuing to learn more about terrain rendering, and so far I've managed to load in a heightmap and render it as a tessellated wireframe (following Frank Luna's DX11 book). However, I'm getting some really weird behavior where a large section of the wireframe is being rendered with a yellow color, even though my pixel shader is hard coded to output white.

The parts of the mesh that are discolored changes as well, as pictured below (mesh is being clipped by far plane).

Here is my pixel shader. As mentioned, I simply hard code it to output white:
float PS(DOUT pin) : SV_Target { return float4(1.0f, 1.0f, 1.0f, 1.0f); } I'm completely lost on what could be causing this, so any help in the right direction would be greatly appreciated. If I can help by providing more information please let me know.

• Hello,
i try to implement voxel cone tracing in my game engine.
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

• 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

• Hi,
I finally managed to get the DX11 emulating Vulkan device working but everything is flipped vertically now because Vulkan has a different clipping space. What are the best practices out there to keep these implementation consistent? I tried using a vertically flipped viewport, and while it works on Nvidia 1050, the Vulkan debug layer is throwing error messages that this is not supported in the spec so it might not work on others. There is also the possibility to flip the clip scpace position Y coordinate before writing out with vertex shader, but that requires changing and recompiling every shader. I could also bake it into the camera projection matrices, though I want to avoid that because then I need to track down for the whole engine where I upload matrices... Any chance of an easy extension or something? If not, I will probably go with changing the vertex shaders.

# DX11 Cannot Create A Constant Buffer

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hi

I'm trying to create a constant buffer (below) using SharpDx which fails.

var textureInfoBuffer = new SharpDX.Direct3D11.Buffer(m_Dx11Device, Utilities.SizeOf<PerFrameTextureInfo>(), ResourceUsage.Default,
BindFlags.ConstantBuffer, CpuAccessFlags.None, ResourceOptionFlags.None, 0);



Structure (PreframeTextureInfo):

using SharpDX;
using System.Runtime.InteropServices;
/// <summary>
/// Per Object constant buffer (matrices)
/// </summary>
[StructLayout(LayoutKind.Sequential)]
public struct PerFrameTextureInfo
{
// texture width
public float Width;

// texture height
public float Height;
}


Texture2D ShaderTexture : register(t0);
SamplerState Sampler = sampler_state    //sampler for doing the texture-lookup
{
Texture = (ShaderTexture);          //apply a texture to the sampler
MipFilter = LINEAR;         //sampler states
MinFilter = LINEAR;
MagFilter = LINEAR;
};

cbuffer PerObject : register(b0)
{
float4x4 ViewProjection;
float4x4 World;
};

cbuffer PerFrameTextureInfo : register(b1)
{
float Width;
float Height;
};


Error Message:

[attachment=32663:sharpdx_CB_Error.PNG]

Now i can't seem to figure out as to why does this fail or what have i done wrong as i manage to create my PerObject buffer for my projection matrices using similiar code.

Any help or suggestions ?

Using C# with SharpDx and Directx11

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A constant buffer has to have a size, that is a multiple of 16 bytes. PerFrameTextureInfo is 8 byte so creation fails, while PerObject is 128 byte.

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You can use static_assert with condition sizeof % 16 == 0 just below structure definition. This way you will get compile time error instead of runtime.

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Thanks for identifying the issue here. as i'm new and learning DirectX do you have any suggestion to fix this ?

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Its not directX problem, its C in general. Just read on "structure alignment" (its very easy) and padding.

For example, having struct with 4x4 matrix and xyz vector would need 1 addition padding float. The 4x4 float matrix takes 64 bytes, it will be placed at offset 0. Next, you want to pack the 3 float vector, at offset 64, taking 12 bytes. The structure is 76 bytes in size then, do you add 1 float (or int, or 4 char array - whatever with size of 4 bytes) and magically the structure grows to 80 bytes :) It is 16 byte aligned, buffer works.

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Ok if i understand correctly then i will need to ensure the structure size is always a multiple of 16. if it isn't then i will need to pad by adding dummy variables.

thus for instance as i have two variable Width and height defined so i will need to make sure i add 2 additional variables even if i don't use them to make them into a multiple of 16.

Is my understanding correct ?

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Yes, but thats only for gpu buffers. If you need own structure for own (not gpu) processing then obviously you do not have to do that... :)

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Ok if i understand correctly then i will need to ensure the structure size is always a multiple of 16. if it isn't then i will need to pad by adding dummy variables.

thus for instance as i have two variable Width and height defined so i will need to make sure i add 2 additional variables even if i don't use them to make them into a multiple of 16.

Is my understanding correct ?

You can skip the headache of manual padding and dummy variables by using attributes to explicitly set the structure size and field offsets:

//Explicit layout kind, specify size (which must be a multiple of 16)
[StructLayout(LayoutKind.Explicit, Size = 16)]
public struct PerFrameTextureInfo
{
[FieldOffset(0)]
public float Width;

[FieldOffset(4)]
public float Height;
}


Source (and also a resource I highly recommend reading): http://timjones.tw/blog/archive/2011/03/08/marshalling-c-structures-into-directd-cbuffers-using