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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 DX11 - Dual Paraboloid Mapping - One Render Pass

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Hi guys,

I'm trying to approach the method of Dual Paraboloid Mapping, the method itself is integrated, now I'm thinking of optimizations, like can it be integrated in one render pass. Recently I have been informed that you can use multiple camera views in one pass with using the geometry shader, and then exporting to different render targets, whether this would be a performance improvement, I can't tell as I have never done it.

Question 1. How can the geometry shader be used to export multiple SV_Positions according to the render targets?

When reading a theoretical and practical paper on Dual Paraboloid Mapping by Jazon Zink, he explained the artifacts that can appear, which I receive myself.

Question 2. Is there a way to fake away these artifacts, or a proper method to?

Thank You, as always.

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I just realized something, when coming close to the vertices, they somehow jump:

So when any vertex come to the corner of the screen, they jump away.

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The implementation for rendering a single pass dual paraboloid map can be found in Hieroglyph 3 (see the MirrorMirror sample).  In there, I use the geometry shader to render both paraboloid maps at once.  To be honest, I never tried to do it in a two pass method, so I can't really give any real information about comparing the speeds.  Some people stay away from the geometry shader at all costs, but I haven't really had any performance problems while using it.  Just as FYI, there is a chapter in Practical Rendering and Computation with Direct3D 11 that deals with setting up the single pass rendering of dual paraboloid maps.

What is probably happening with your vertices is that once they go behind the paraboloid's center point then the method used to find the vertex position puts it on the opposite side of the paraboloid map.  You should detect when this is the case and either clip the pixels affected or clamp the vertex position to the plane where z = 0 in paraboloid space.

Fixing the issues with primitive size is not really possible unless you tessellate things a bit better.  You could use a stronger LOD system, or possibly use the tessellation stages to improve the tessellation based on paraboloid map size.  But again, you may run into performance problems with the additional stages being active...

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About the issue with the vertices, it still appears, here's what I do:

VS: // After applying world*view*proj
output.position = output.position / output.position.w;

// The decider between the front and back side
output.position.z *= _dpmSetting;

float L = length( output.position.xyz );
output.position = output.position / L;

output.z_value = output.position.z;

output.position.z = output.position.z + 1;
output.position.x = output.position.x / output.position.z;
output.position.y = output.position.y / output.position.z;

output.position.z = L / 500;							// set a depth value for correct z-buffering
output.position.w = 1;									// set w to 1 so there is no w divide

PS:
clip( input.z_value );


But no luck.

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Do you have a culling mode enabled?  Either back face or front face culling?

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This is how I initialize my D3D11_RASTERIZER_DESC stage:

D3D11_RASTERIZER_DESC rasterizerState;
rasterizerState.FillMode = D3D11_FILL_SOLID;
rasterizerState.CullMode = D3D11_CULL_BACK;
rasterizerState.FrontCounterClockwise = false;
rasterizerState.DepthBias = false;
rasterizerState.DepthBiasClamp = 0;
rasterizerState.SlopeScaledDepthBias = 0;
rasterizerState.DepthClipEnable = true;
rasterizerState.ScissorEnable = true;
rasterizerState.MultisampleEnable = false;
rasterizerState.AntialiasedLineEnable = false;


But nothing changed, though I may have done it wrong.

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Well after countless tries, I can't seem to solve the jumping of vertices.

output.position = output.position / output.position.w;

When this line is removed the problem no longer persists, but again, that creates another issue as the map doesn't become correct.

Creation of D3D11_RASTERIZER_DESC :
D3D11_RASTERIZER_DESC rasterizerState;
rasterizerState.FillMode = D3D11_FILL_SOLID;
rasterizerState.CullMode = D3D11_CULL_BACK;
rasterizerState.FrontCounterClockwise = false;
rasterizerState.DepthBias = false;
rasterizerState.DepthBiasClamp = 0;
rasterizerState.SlopeScaledDepthBias = 0;
rasterizerState.DepthClipEnable = true;
rasterizerState.ScissorEnable = true;
rasterizerState.MultisampleEnable = false;
rasterizerState.AntialiasedLineEnable = false;

dev->CreateRasterizerState(&rasterizerState, &RsRMAP);


VS
output.position = mul(position, worldMatrix);
output.position = mul(output.position, viewMatrix);
output.position = mul(output.position, projectionMatrix);

output.position = output.position / output.position.w;

// The decider between the front and back side
output.position.z *= _dpmSetting; // 1 front || -1 back

// Determine the distance between the paraboloid origin and the vertex.
float L = length( output.position.xyz );

// Normalize the vector to the vertex
output.position = output.position / L;

// Save the z-component of the normalized vector
output.z_value = output.position.z;

output.position.z = output.position.z + 1;
output.position.x = output.position.x / output.position.z;
output.position.y = output.position.y / output.position.z;
output.position.z = (L - 0.1)/(500.0-0.1);

output.position.w = 1;

PS
clip( input.z_value );


Now what on the earth have I done wrong... again...

Edited by Migi0027

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As a test, I would say to change the color of the vertices based on their output.z_value attribute.  If the value is greater than 0, then use one color, and if it is less than 0 use another color.  This will help you identify which vertices you should be displaying and which ones should not be.  I am willing to bet that the ones that you shouldn't see are the ones jumping to the other side.  This geometry should be captured in the other paraboloid map, and hence be clipped from the current one.  In fact, that is why it jumps - because the paraboloid transformation is only correct when z > 0!

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Result:

HLSL:

if ( input.z_value > 0)
{
output.Diffuse = float4(0, 1, 0, 1);
}
else
{
output.Diffuse = float4(1, 0, 0, 1);
}

clip( input.z_value );

output.Lighting = float4(1, 1, 1, 1);

return output;


I must be doing something really stupid right now.