Jump to content

  • Log In with Google      Sign In   
  • Create Account

We're offering banner ads on our site from just $5!

1. Details HERE. 2. GDNet+ Subscriptions HERE. 3. Ad upload HERE.

Camera axis always inverted somehow

Old topic!
Guest, the last post of this topic is over 60 days old and at this point you may not reply in this topic. If you wish to continue this conversation start a new topic.

  • You cannot reply to this topic
3 replies to this topic

#1 lipsryme   Members   -  Reputation: 1043


Posted 12 February 2013 - 05:42 PM

I've come across this stupid problem with my camera and it is driving me nuts biggrin.png

Maybe someone has an idea of what's going wrong...



This is basically a standard camera I create:

StaticCamera::StaticCamera(CameraDescription desc) : BaseCamera(desc)
        // Assign values
	this->fov = desc.FoV;
	this->aspectRatio = desc.Aspect;
	this->nearClip = desc.nearClip;
	this->farClip = desc.farClip;

	this->camPosition = XMFLOAT4(desc.cameraPosition.x, desc.cameraPosition.y, desc.cameraPosition.z,           1.0f);
	this->camTarget = XMFLOAT4(desc.cameraTarget.x, desc.cameraTarget.y, desc.cameraTarget.z, 1.0f);
	this->camUp = XMFLOAT4(desc.cameraUp.x, desc.cameraUp.y, desc.cameraUp.z, 1.0f);

	// Create our perspective projection

void StaticCamera::CreateViewProjection()
    XMVECTOR tempPos = XMLoadFloat4(&this->camPosition);
    XMVECTOR tempTarget = XMLoadFloat4(&this->camTarget);
    XMVECTOR tempUp = XMLoadFloat4(&this->camUp);

    XMMATRIX tempView = XMMatrixLookToLH(tempPos, tempTarget, tempUp);
    XMMATRIX tempProj = XMMatrixPerspectiveFovLH(this->fov, this->aspectRatio,
                                                 this->nearClip, this->farClip);

    XMMATRIX tempViewProjection = XMMatrixMultiply(tempView, tempProj);

    // Store results
    XMStoreFloat4x4(&this->viewProjection, tempViewProjection);
    XMStoreFloat4x4(&this->view, tempView);
    XMStoreFloat4x4(&this->projection, tempProj);



Here I set the data to my constant buffer:

D3D11_MAPPED_SUBRESOURCE mappedResource;

		// Lock the constant buffer so it can be written to
		this->deviceContext->Map(this->cbGBTransformsConstBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mappedResource);

		// Get a pointer to the data in the constant buffer.
		cbGBufferTransforms* pTransformData = (cbGBufferTransforms*)mappedResource.pData;

		// Set each objects world transform matrix and draw it
		this->cbGBTransforms.World = this->opaquePrimitives.at(i)->GetTransform();
		XMMATRIX transposed = XMLoadFloat4x4(&this->cbGBTransforms.World);
		XMMATRIX worldViewProj = transposed * this->engine->GetCamera()->GetViewProjectionMatrix();
		XMStoreFloat4x4(&pTransformData->WorldViewProjection, XMMatrixTranspose(worldViewProj));

// Unlock the constant buffer
        this->deviceContext->Unmap(this->cbGBTransformsConstBuffer, 0);


   And my shader for the geometry:
struct VSI
	float4 Position  : POSITION;
	float2 UV		 : TEXCOORD0;
	float3 Normal    : NORMAL;
	float3 BiTangent : BINORMAL;
	float3 Tangent   : TANGENT;

PSI VS(VSI input)
	PSI output = (PSI)0;

	// Transform geometry for 3D projection
	output.Position = mul(input.Position, WorldViewProjection);

	// Transform to clip space position of previous frame
	output.PrevPositionCS = mul(float4(input.Position.xyz, 1.0f), PrevWorldViewProjection);
	output.PositionCS = output.Position;

	// Modify Tiling factor of textures
	output.UV = input.UV * TexCoordModifier;

	// Transform Tangent-BiTangent-Normal into world space
	output.Tangent = mul(input.Tangent, (float3x3)World);
	output.BiTangent = mul(input.BiTangent, (float3x3)World);
	output.Normal = mul(input.Normal, (float3x3)World);

	return output;


  Now for some reason my camera is always inverted (upside down and when using camera movement rotation is also wrong/inverted).



  Looks like this:


Edited by lipsryme, 12 February 2013 - 05:43 PM.


#2 smasherprog   Members   -  Reputation: 432


Posted 12 February 2013 - 09:23 PM

try removing the transpose from this line


XMStoreFloat4x4(&pTransformData->WorldViewProjection, XMMatrixTranspose(worldViewProj));


making it


XMStoreFloat4x4(&pTransformData->WorldViewProjection, worldViewProj);

Wisdom is knowing when to shut up, so try it.
--Game Development http://nolimitsdesigns.com: Reliable UDP library, Threading library, Math Library, UI Library. Take a look, its all free.

#3 lipsryme   Members   -  Reputation: 1043


Posted 13 February 2013 - 06:50 AM

Nope that doesn't seem to work.

Thing is the shadow map is the only thing that projects correctly, I have no idea why.

#4 Ashaman73   Crossbones+   -  Reputation: 7987


Posted 13 February 2013 - 07:33 AM


the tempView matrix you construct in the CreateViewProjection method is the world orientation matrix of the camera, but you need to convert the world space into view space. Therefor invert the camera matrix to get the view matrix. The final transformation should look like


final_position = Proj * inv(Camera) * Model * position


I think that the transpose is not necessary either (transpose is often used to invert the rotation matrix part of an orthogonal matrix, but you need to take care about the position and scaling too).

Edited by Ashaman73, 13 February 2013 - 07:35 AM.

Old topic!
Guest, the last post of this topic is over 60 days old and at this point you may not reply in this topic. If you wish to continue this conversation start a new topic.