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• ### Similar Content

• By Jiraya
For a 2D game, does using a float2 for position increases performance in any way?
I know that in the end the vertex shader will have to return a float4 anyway, but does using a float2 decreases the amount of data that will have to be sent from the CPU to the GPU?

• By ucfchuck
I am feeding in 16 bit unsigned integer data to process in a compute shader and i need to get a standard deviation.
So I read in a series of samples and push them into float arrays
float vals1[9], vals2[9], vals3[9], vals4[9]; int x = 0,y=0; for ( x = 0; x < 3; x++) { for (y = 0; y < 3; y++) { vals1[3 * x + y] = (float) (asuint(Input1[threadID.xy + int2(x - 1, y - 1)].x)); vals2[3 * x + y] = (float) (asuint(Input2[threadID.xy + int2(x - 1, y - 1)].x)); vals3[3 * x + y] = (float) (asuint(Input3[threadID.xy + int2(x - 1, y - 1)].x)); vals4[3 * x + y] = (float) (asuint(Input4[threadID.xy + int2(x - 1, y - 1)].x)); } } I can send these values out directly and the data is as expected

Output1[threadID.xy] = (uint) (vals1[4] ); Output2[threadID.xy] = (uint) (vals2[4] ); Output3[threadID.xy] = (uint) (vals3[4] ); Output4[threadID.xy] = (uint) (vals4[4] ); however if i do anything to that data it is destroyed.
vals1[4] = vals1[4]/2;
or a
vals1[4] = vals[1]-vals[4];
the data is gone and everything comes back 0.

How does one go about converting a uint to a float and performing operations on it and then converting back to a rounded uint?
• 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

# DX11 [D3D11] Newbie Help with DrawIndexed

This topic is 661 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

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I have recently gone through all the tutorials at http://www.rastertek.com/tutdx11s2.html  to learn DirectX11 pipeline.    I have gotten a pretty good grasp of how the pipeline works and what the code is doing.  (though I know very little about all the various options chosen in the initialization process, or what possible changes could be made yet).   The code is quite long but it basically sets everything up to draw a single textured triangle.  I'm having trouble getting this code to draw a 2nd triangle.

I've searched the forums for help but mostly came up with D3D9 code example which using a different function to draw the primitives.

Here is the relevent code:

// Set the number of vertices in the vertex array.
m_vertexCount = 3;

// Set the number of indices in the index array.
m_indexCount = 3;

// Load the vertex array with data.
vertices[0].position = XMFLOAT3(-1.0f, 1.0f, 0.0f);  // Bottom left.
vertices[0].texture = XMFLOAT2(0.0f, 0.0f);

vertices[1].position = XMFLOAT3(1.0f, 1.0f, 0.0f);  // Top middle.
vertices[1].texture = XMFLOAT2(1.0f, 0.0f);

vertices[2].position = XMFLOAT3(-1.0f, -1.0f, 0.0f);  // Bottom right.
vertices[2].texture = XMFLOAT2(0.0f, 1.0f);

// Load the index array with data.
indices[0] = 0;  // Bottom left.
indices[1] = 1;  // Top middle.
indices[2] = 2;  // Bottom right.

// Along with hundres of lines of initialization and run-time code not shown
// This line draws the triangle correctly.

deviceContext->DrawIndexed(indexCount, 0, 0);



Now if I change it to this:

// Set the number of vertices in the vertex array.
m_vertexCount = 4;

// Set the number of indices in the index array.
m_indexCount = 6;

// Load the vertex array with data.
vertices[0].position = XMFLOAT3(-1.0f, 1.0f, 0.0f);  // Bottom left.
vertices[0].texture = XMFLOAT2(0.0f, 0.0f);

vertices[1].position = XMFLOAT3(1.0f, 1.0f, 0.0f);  // Top middle.
vertices[1].texture = XMFLOAT2(1.0f, 0.0f);

vertices[2].position = XMFLOAT3(-1.0f, -1.0f, 0.0f);  // Bottom right.
vertices[2].texture = XMFLOAT2(0.0f, 1.0f);

vertices[3].position = XMFLOAT3(1.0f, -1.0f, 0.0f);  // Bottom right.
vertices[3].texture = XMFLOAT2(1.0f, 1.0f);

// Load the index array with data.
indices[0] = 0;  // Bottom left.
indices[1] = 1;  // Top middle.
indices[2] = 2;  // Bottom right.
indices[3] = 1;
indices[4] = 2;
indices[5] = 3;

// Along with hundres of lines of initialization and run-time code not shown
// This line draws the triangle correctly.

deviceContext->DrawIndexed(indexCount, 0, 0);

It still only draws the first traingle, and never draws. the 2nd.   I know IndexCount is being set to 6.    I also know the index buffer is working correctly with the vertex buffer because I can change:   indices[2]=2  to indices[2]=3    and a different triangle gets drawn.   I'm curious if anyone familiar with this tutorial series, or just D3DX11 in general might clue me in on how DrawIndexed works, or if there is some obvious setting somehwere to let it know it needs to draw more than 1 triangle?

Edited by drwhat

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Just a quick guess, Is backface culling enabled?  That might be what is making the second triangle "disappear".

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Thank you that was exactly the problem.   I switched the CULL_MODE method in the raster from D3D11_CULL_BACK to D3D11_CULL_NONE.

So I guess I'm not understanding the Cull process.  Why would the 2nd triangle in my example be culled?  The 4 vertices I chose are just form a square (in fact when i changed the culling mode a square shows up perfectly with my square texture perfectly displayed on the 2 triangles).   What is it about the 2nd triangle that causes DirectX to determine its backward facing.    Though i will say it was consistent.  When I tried using CULL_FRONT  the first triangle disappeared and only the 2nd triangle was drawn.

Edit:   I guess it uses some Normal of the 3 triangles, and when the normal would point directly towards or away from the camera it must be  based on the order of the 3 vertex.  When I swap the order that the vertices are drawn, it will appear and disappear if culling is set to FRONT or BACK.

Edited by drwhat

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Try changing indices to this.

indices[0] = 0;
indices[1] = 1;
indices[2] = 2;
indices[3] = 2;
indices[4] = 1;
indices[5] = 3;

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It's all in whether you define the vertices in clockwise or counterclockwise order. That determines the normal of the face. And that determines which side is which for back-face (or front-face) culling.

Wow, a short post. I didn't know I even could make a short post. ;-)