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EpicZa's avatar
EpicZa
Honored Guest
11 years ago

Looking left actually looks Right vice versa OpenGL

Im close, so close! But looking left actually looks right! I tried taking out the .inverted but that just means that look up/down are the wrong way round, I tried computing the up vector from the cross of the right and direction vectors, but same thing. I know its to do with my up vector I just can't figure out how to fix it!

Any help appreciated. 

for (int eyeIndex = 0; eyeIndex < ovrEye_Count; eyeIndex++)
		{

			ovrEyeType eye = hmd->EyeRenderOrder[eyeIndex];
			eyeRenderPose[eye] = ovrHmd_GetHmdPosePerEye(hmd, eye);

			//Get Projection and ModelView matrici from SDK..
			Matrix4f  ovrProjection             = Matrix4f(ovrMatrix4f_Projection(eyeRenderDesc[eye].Fov, 0.01f, 100.0f, true));
			glm::mat4 glmProjection             = fromOvr(ovrProjection);

			//Translate for specific eye..
			Matrix4f  ovrTranslatEyeViewOffSet  = Matrix4f::Translation(eyeRenderDesc[eye].HmdToEyeViewOffset);
			glm::mat4 glmTranslatEyeViewOffSet  = fromOvr(ovrTranslatEyeViewOffSet);

			Matrix4f  ovrOrientation            = Matrix4f(Quatf(eyeRenderPose[eye].Orientation).Inverted());
			glm::mat4 glmOrientation            = fromOvr(ovrOrientation);

			Matrix4f  ovrTranslatEyeRenderPos   = Matrix4f::Translation(-Vector3f(eyeRenderPose[eye].Position));
			glm::mat4 glmTranslatEyeRenderPos   = fromOvr(ovrTranslatEyeRenderPos);
			
			glm::vec3 AdjustedPosition          = glm::vec3(glmTranslatEyeRenderPos[3]);

                        AdjustedPosition			        += glm::vec3(glmTranslatEyeRenderPos[3]);


			//Not currently using
glm::vec3 CurrentRightDirection	   = glm::vec3(glmOrientation[0][0], glmOrientation[0][1], glmOrientation[0][2]);
			

glm::vec3 CurrentUpDirection	   = glm::vec3(glmOrientation[1][0], glmOrientation[1][1], glmOrientation[1][2]);
		
	
glm::vec3 CurrentViewingDirection  = glm::vec3(glmOrientation[2][0], glmOrientation[2][1], glmOrientation[2][2]);

			//Camera Matrix
			glm::mat4 glmView = glm::lookAt(
											    AdjustedPosition,
												AjdustedPosition  + CurrentViewingDirection,
											    CurrentUpDirection
																						    );

			glm::mat4 MVP     = glmProjection * glmTranslatEyeViewOffSet * glmView * glm::mat4(1.0f);
			
			glUniformMatrix4fv(MatrixID, 1, GL_FALSE, &MVP[0][0]);

			glBindVertexArray(VertexArrayCube);


			glViewport(eyeRenderViewport[eye].Pos.x, eyeRenderViewport[eye].Pos.y, eyeRenderViewport[eye].Size.w, eyeRenderViewport[eye].Size.h);
			
			glDrawArrays(GL_TRIANGLES, 0, 12 * 3);

		}


EDIT: (Changed code to add translations of HMD) Then also noticed that the up/down translation of the oculus along the y axis are inverted too, so raising the oculus to the roof actually lowers the view in the scene.

3 Replies

  • kojack's avatar
    kojack
    MVP
    11 years ago
    Matrix4f  ovrOrientation            = Matrix4f(Quatf(eyeRenderPose[eye].Orientation).Inverted());

    Why are you inverting the orientation of each eye pose? That would make it look in the opposite direction.
  • EpicZa's avatar
    EpicZa
    Honored Guest
    11 years ago
    "kojack" wrote:
    Matrix4f  ovrOrientation            = Matrix4f(Quatf(eyeRenderPose[eye].Orientation).Inverted());

    Why are you inverting the orientation of each eye pose? That would make it look in the opposite direction.


    Ok I was doing it to reduce my problems from two to one axis'. But you got me thinking and here is what i've done now:

    			Matrix4f  ovrOrientation            = Matrix4f(Quatf(eyeRenderPose[eye].Orientation));// .Inverted();
    			glm::mat4 glmOrientation            = fromOvr(ovrOrientation);

    			glm::mat4 invertOrientation = glm::mat4{ -1.0f, 0.0f, 0.0f, 0.0f,
    				0.0f, 1.0f, 0.0f, 0.0f,
    				0.0f, 0.0f, -1.0f, 0.0f,
    				0.0f, 0.0f, 0.0f, 1.0f };

    			glmOrientation = glmOrientation * invertOrientation;


    Rotations all work perfectly, just have to sort out the translations.

    Cheerss!