public void findHMDTextureSize() {
        // Texture sizes
        float pixelScaling = 1.0f; // pixelsPerDisplayPixel

        OVRSizei leftTextureSize = OVRSizei.malloc();
        ovr_GetFovTextureSize(session, ovrEye_Left, fovPorts[ovrEye_Left], pixelScaling, leftTextureSize);

        OVRSizei rightTextureSize = OVRSizei.malloc();
        ovr_GetFovTextureSize(session, ovrEye_Right, fovPorts[ovrEye_Right], pixelScaling, rightTextureSize);

        if (leftTextureSize.w() != rightTextureSize.w()) {
            throw new IllegalStateException("Texture sizes do not match [horizontal]");
        }
        if (leftTextureSize.h() != rightTextureSize.h()) {
            throw new IllegalStateException("Texture sizes do not match [vertical]");
        }

        textureW = leftTextureSize.w();
        textureH = leftTextureSize.h();

        leftTextureSize.free();
        rightTextureSize.free();
    }
Frame buffers we can draw into.
jme3-vr/src/main/java/com/jme3/input/vr/oculus/OculusVR.java