glm matrix conversion for DirectX
- by niktehpui
For on of the coursework specification I need to work with DirectX, so I tried to implement a DirectX Renderer in my small cross-platform framework (to have it optionally available for Windows). Since I want to stick to my dependencies I want use glm for vector/matrix/quaternions math.
The vectors seem to be fully compatible with DirectX, but the glm::mat4 is not working properly in DirectX Effects Framework. I assumed the reason is that DirectX uses row majors layouts and OpenGL column majors (although if I remember right internally in HLSL DX uses column major as well),
so I transposed the matrix, but I still get no proper results compared to using XNA-Math.
XNA-Version of the code (works):
XMMATRIX world = XMMatrixIdentity();
XMMATRIX view = XMMatrixLookAtLH(XMVectorSet(5.0, 5.0, 5.0, 1.0f), XMVectorZero(), XMVectorSet(0.0f, 1.0f, 0.0f, 0.0f));
XMMATRIX proj = XMMatrixPerspectiveFovLH(0.25f*3.14f, 1.25f, 1.0f, 1000.0f);
XMMATRIX worldViewProj = world*view*proj;
m_fxWorldViewProj->SetMatrix(reinterpret_cast<float*>(&worldViewProj));
This works flawlessly and displays the expected colored cube.
GLM-Version (does not work):
glm::mat4 world(1.0f);
glm::mat4 view = glm::lookAt(glm::vec3(5.0f, 5.0f, 5.0f), glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, 1.0f, 0.0f));
glm::mat4 proj = glm::perspective(0.25f*3.14f, 1.25f, 1.0f, 1000.0f);
glm::mat4 worldViewProj = glm::transpose(world*view*proj);
m_fxWorldViewProj->SetMatrix(glm::value_ptr(worldViewProj));
Displays nothing, screen stays black.
I really would like to stick to glm on all platforms.
