Questions tagged [directxmath]
DirectXMath API provides common linear algebra and graphics math operations to DirectX applications
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What's the relationship between the actor's pose and shape's pose in PhysX?
I have 2 Meshes and I want to add physics to them. The first is a primitive box, the second is a terrain.
The box and terrain are made with DirectXMath
Using the PhysX library, I made a copy of the ...
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What is wrong with my terrain lighting?
I've just implemented a simple algorithm to calculate terrain vertex normals and I'm using diffuse and ambient light currently, but for some reason the squares that make up my terrain are visible when ...
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XMMATRIX performance
Dears,
I am facing a performance problem when I try to access cell 42 and 43 in XMMATRIX define in DirectXMath.h. The frames dropped by 100 FPS.
Here is my code:
...
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What exactly does XMMatrixPerspective{L,R}H do?
There are generally three functions to create a perspective matrix in DirectXMath, XMMatrixPerspective{L,R}H, ...
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2d Scale width and height based on distance
I'm drawing a health bar on top of each player. I transform 3d position to 2d. I would like to draw it smaller when distance increases. Any simple math for that? Let's say bar width is 30 and height ...
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Transforming quaternion between coordinate systems [duplicate]
Working in DirectX (with DirectXMath objects): If I have the rotation of an object relative to some coordinate space as quaternion Q, and I have a transformation matrix tx from that coordinate space ...
- 113
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how to debug calculating tangent space
[][]2
there's problem calculating tangent space and look....
it seems there is no problem with UV code and my shader is 100% no problem. I just copy and pasted tutorial code which works well..
I ...
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Why doesn't TriangleTests::Intersects from DirectXMath work correctly?
I am currently looking through the Introduction to 3D Game Programming with Direct X 11 by Frank Luna and I'm trying to implement the ray-triangle intersections. I already have a ray firing when the ...
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Is there something similar to XMFLOAT2 that has its operators overloaded?
Since XMFLOAT2 is just a structure, I'm sure it does not have operator overloading which is what I need to make things a lot simpler. Is there something like ...
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How to clip cut-off using different frustrum than that of original camera? How to cut plane by pyramid shape?
SOURCE : http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2012/10/Mitchell_LightShafts.pdf
This process is part of creating light draft effect. And I am suggested to do the described process in ...
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Difference between column- and row vector matrix multiplication (vector transform)
Let's say we have a 4-by-4 matrix \$A\$ which represents some transformation.
We can use this matrix to transform a vector in two ways.
\$Ax\$ by assuming \$x\$ is a 4-by-1 column vector.
\$xA\$ by ...
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Calculate matrix transformation components separately
It is possible to calculate the translation, rotation and scale that were used to build a matrix?
I mean if I have a matrix M can I calculate the rotation, scale, ...
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How to rotate camera using mouse?
I'm looking for a basic example of rotating camera using the mouse. the only problem is I'm not sure of how to rotating the camera around it target. should i do this by an algorithm or is there a ...
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How can I get projected coordinates of vertex on screen
I want to check picking for faces and for that I need projected X Y coordinates of my vertexes in -1 to 1 range:
For that I multiply my vertex array with matrices and then get projected triangle ...
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Simulating aircraft movement with DirectX 9 [closed]
How would I go about simulating a planes movement in DirectX 9 using transforms (i.e. matrices).
For example flying around an open space. When it moves it faces the direction it is going and ...
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How do I correctly multiply an XMMATRIX by a scalar?
Using DirectXMath and its XMMATRIX structure in C++ and Direct X 11, how does one multiply that matrix structure by a single float scalar?
I want to implement the ...
- 11
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Can I use memcpy() with XMMATRIX?
I.e. can I do this:
XMMATRIX dxMat;
Matrix myMat;
std::memcpy(&myMat, &dxMat, sizeof(XMMATRIX));
std::memcpy(&dxMat, &myMat, sizeof(XMMATRIX));
<...
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Copy unaligned XMVECTOR and use the copy?
I know XMVECTOR has to be 16-byte-aligned and therefore shouldn't be a member of a class (unless I ensure the alignment). However, can I do sth like this?
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