jMonkeyEngine/jme3-vr/src/main/java/com/jme3/util/VRViewManagerOculus.java

/*
 * Copyright (c) 2009-2017 jMonkeyEngine
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
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 *
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
 *   may be used to endorse or promote products derived from this software
 *   without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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package com.jme3.util;

import com.jme3.app.VREnvironment;
import com.jme3.input.vr.OculusVR;
import com.jme3.input.vr.VRAPI;
import com.jme3.math.ColorRGBA;
import com.jme3.math.Quaternion;
import com.jme3.math.Vector2f;
import com.jme3.math.Vector3f;
import com.jme3.renderer.Camera;
import com.jme3.renderer.ViewPort;
import com.jme3.scene.Spatial;
import com.jme3.texture.*;

import java.nio.IntBuffer;
import java.util.Iterator;
import java.util.logging.Logger;

import org.lwjgl.ovr.*;

import static org.lwjgl.ovr.OVR.*;
import static org.lwjgl.ovr.OVRErrorCode.*;

/**
 * A rendering system for Oculus's LibOVR API.
 *
 * @author Campbell Suter <[email protected]>
 */
public class VRViewManagerOculus extends AbstractVRViewManager {

    private static final Logger LOG = Logger.getLogger(VRViewManagerOculus.class.getName());

    private final VREnvironment environment;
    private final OculusVR hardware;

    // Copied from OSVR
    //final & temp values for camera calculations
    private final Vector3f finalPosition = new Vector3f();
    private final Quaternion finalRotation = new Quaternion();
    private final Vector3f hmdPos = new Vector3f();
    private final Quaternion hmdRot = new Quaternion();

    public VRViewManagerOculus(VREnvironment environment) {
        this.environment = environment;

        VRAPI hardware = environment.getVRHardware();
        if (!(hardware instanceof OculusVR)) {
            throw new IllegalStateException("Cannot use Oculus VR view manager on non-Oculus hardware state!");
        }

        this.hardware = (OculusVR) hardware;

        if (!environment.compositorAllowed()) {
            throw new UnsupportedOperationException("Cannot render without compositor on LibOVR");
        }
    }

    @Override
    public void initialize() {
        setupCamerasAndViews();
    }

    private long session() {
        return hardware.getSessionPointer();
    }

    @Override
    public void update(float tpf) {
        // TODO

        hardware.updatePose();

        // TODO deduplicate
        if (environment != null) {
            // grab the observer
            Object obs = environment.getObserver();
            Quaternion objRot;
            Vector3f objPos;
            if (obs instanceof Camera) {
                objRot = ((Camera) obs).getRotation();
                objPos = ((Camera) obs).getLocation();
            } else {
                objRot = ((Spatial) obs).getWorldRotation();
                objPos = ((Spatial) obs).getWorldTranslation();
            }
            // grab the hardware handle
            VRAPI dev = environment.getVRHardware();
            if (dev != null) {
                // update the HMD's position & orientation
                dev.getPositionAndOrientation(hmdPos, hmdRot);
                if (obs != null) {
                    // update hmdPos based on obs rotation
                    finalRotation.set(objRot);
                    finalRotation.mult(hmdPos, hmdPos);
                    finalRotation.multLocal(hmdRot);
                }

                finalizeCamera(dev.getHMDVectorPoseLeftEye(), objPos, leftCamera);
                finalizeCamera(dev.getHMDVectorPoseRightEye(), objPos, rightCamera);
            } else {
                leftCamera.setFrame(objPos, objRot);
                rightCamera.setFrame(objPos, objRot);
            }

            if (environment.hasTraditionalGUIOverlay()) {
                // update the mouse?
                environment.getVRMouseManager().update(tpf);

                // update GUI position?
                if (environment.getVRGUIManager().wantsReposition || environment.getVRGUIManager().getPositioningMode() != VRGUIPositioningMode.MANUAL) {
                    environment.getVRGUIManager().positionGuiNow(tpf);
                    environment.getVRGUIManager().updateGuiQuadGeometricState();
                }
            }
        } else {
            throw new IllegalStateException("This VR view manager is not attached to any VR environment.");
        }
    }

    /**
     * Place the camera within the scene.
     *
     * @param eyePos      the eye position.
     * @param obsPosition the observer position.
     * @param cam         the camera to place.
     */
    private void finalizeCamera(Vector3f eyePos, Vector3f obsPosition, Camera cam) {
        finalRotation.mult(eyePos, finalPosition);
        finalPosition.addLocal(hmdPos);
        if (obsPosition != null) {
            finalPosition.addLocal(obsPosition);
        }
        finalPosition.y += getHeightAdjustment();
        cam.setFrame(finalPosition, finalRotation);
    }

    @Override
    public void render() {
        for (int eye = 0; eye < 2; eye++) {
            // TODO do we need this? Don't we set the camera positions ourselves?
            OVRPosef eyePose = hardware.getEyePosesPtr()[eye];
            hardware.getLayer0().RenderPose(eye, eyePose);

            IntBuffer currentIndexB = BufferUtils.createIntBuffer(1);
            ovr_GetTextureSwapChainCurrentIndex(session(), hardware.getChain(), currentIndexB);
            int index = currentIndexB.get();

            (eye == ovrEye_Left ? leftViewPort : rightViewPort).setOutputFrameBuffer(hardware.getFramebuffers()[index]);
        }

        // Now the game will render into the buffers given to us by LibOVR
    }

    @Override
    public void postRender() {
        // We're done with our textures now - the game is done drawing into them.
        ovr_CommitTextureSwapChain(session(), hardware.getChain());

        // Send the result to the HMD
        int result = ovr_SubmitFrame(session(), 0, null, hardware.getLayers());
        if (result != ovrSuccess) {
            throw new IllegalStateException("Failed to submit frame!");
        }
    }

    /*
     *********************************************************
     *  Show's over, now it's just boring camera stuff etc.  *
     *********************************************************
     */

    /**
     * Set up the cameras and views for each eye and the mirror display.
     */
    private void setupCamerasAndViews() {
        // TODO: Use LobOVR IPD etc
        if (environment != null) {
            // get desired frustrum from original camera
            Camera origCam = environment.getCamera();
            float fFar = origCam.getFrustumFar();
            float fNear = origCam.getFrustumNear();

            // restore frustrum on distortion scene cam, if needed
            if (environment.isInstanceRendering()) {
                leftCamera = origCam;
            } else if (environment.compositorAllowed() == false) {
                origCam.setFrustumFar(100f);
                origCam.setFrustumNear(1f);
                leftCamera = origCam.clone();
                prepareCameraSize(origCam, 2f);
            } else {
                leftCamera = origCam.clone();
            }

            getLeftCamera().setFrustumPerspective(environment.getDefaultFOV(), environment.getDefaultAspect(), fNear, fFar);

            prepareCameraSize(getLeftCamera(), 1f);
            if (environment.getVRHardware() != null) {
                getLeftCamera().setProjectionMatrix(environment.getVRHardware().getHMDMatrixProjectionLeftEye(getLeftCamera()));
            }
            //org.lwjgl.opengl.GL11.glEnable(org.lwjgl.opengl.GL30.GL_FRAMEBUFFER_SRGB);

            if (!environment.isInstanceRendering()) {
                leftViewPort = setupViewBuffers(getLeftCamera(), LEFT_VIEW_NAME);
                rightCamera = getLeftCamera().clone();
                if (environment.getVRHardware() != null) {
                    getRightCamera().setProjectionMatrix(environment.getVRHardware().getHMDMatrixProjectionRightEye(getRightCamera()));
                }
                rightViewPort = setupViewBuffers(getRightCamera(), RIGHT_VIEW_NAME);
            } else if (environment.getApplication() != null) {

                LOG.severe("THIS CODE NEED CHANGES !!!");
                leftViewPort = environment.getApplication().getViewPort();
                //leftViewport.attachScene(app.getRootNode());
                rightCamera = getLeftCamera().clone();
                if (environment.getVRHardware() != null) {
                    getRightCamera().setProjectionMatrix(environment.getVRHardware().getHMDMatrixProjectionRightEye(getRightCamera()));
                }

                org.lwjgl.opengl.GL11.glEnable(org.lwjgl.opengl.GL30.GL_CLIP_DISTANCE0);

                //FIXME: [jme-vr] Fix with JMonkey next release
                //RenderManager._VRInstancing_RightCamProjection = camRight.getViewProjectionMatrix();
                // TODO: Add LibOVR support
                // setupFinalFullTexture(environment.getApplication().getViewPort().getCamera());
            } else {
                throw new IllegalStateException("This VR environment is not attached to any application.");
            }

            // setup gui
            environment.getVRGUIManager().setupGui(getLeftCamera(), getRightCamera(), getLeftViewPort(), getRightViewPort());

            if (environment.getVRHardware() != null) {
                // call these to cache the results internally
                environment.getVRHardware().getHMDMatrixPoseLeftEye();
                environment.getVRHardware().getHMDMatrixPoseRightEye();
            }
        } else {
            throw new IllegalStateException("This VR view manager is not attached to any VR environment.");
        }
    }

    private void prepareCameraSize(Camera cam, float xMult) {
        // TODO this function is identical to that in VRViewManagerOpenVR; merge the two.
        if (environment != null) {
            if (environment.getApplication() != null) {
                Vector2f size = new Vector2f();
                VRAPI vrhmd = environment.getVRHardware();

                if (vrhmd == null) {
                    size.x = 1280f;
                    size.y = 720f;
                } else {
                    vrhmd.getRenderSize(size);
                }

                if (size.x < environment.getApplication().getContext().getSettings().getWidth()) {
                    size.x = environment.getApplication().getContext().getSettings().getWidth();
                }
                if (size.y < environment.getApplication().getContext().getSettings().getHeight()) {
                    size.y = environment.getApplication().getContext().getSettings().getHeight();
                }

                if (environment.isInstanceRendering()) {
                    size.x *= 2f;
                }

                // other adjustments
                size.x *= xMult;
                size.x *= getResolutionMuliplier();
                size.y *= getResolutionMuliplier();

                if (cam.getWidth() != size.x || cam.getHeight() != size.y) {
                    cam.resize((int) size.x, (int) size.y, false);
                }
            } else {
                throw new IllegalStateException("This VR environment is not attached to any application.");
            }
        } else {
            throw new IllegalStateException("This VR view manager is not attached to any VR environment.");
        }
    }

    private ViewPort setupViewBuffers(Camera cam, String viewName) {
        // TODO this function is identical to that in VRViewManagerOpenVR; merge the two.
        if (environment != null) {
            if (environment.getApplication() != null) {
                // create offscreen framebuffer
                FrameBuffer offBufferLeft = new FrameBuffer(cam.getWidth(), cam.getHeight(), 1);
                //offBufferLeft.setSrgb(true);

                //setup framebuffer's texture
                Texture2D offTex = new Texture2D(cam.getWidth(), cam.getHeight(), Image.Format.RGBA8);
                offTex.setMinFilter(Texture.MinFilter.BilinearNoMipMaps);
                offTex.setMagFilter(Texture.MagFilter.Bilinear);

                //setup framebuffer to use texture
                offBufferLeft.setDepthBuffer(Image.Format.Depth);
                offBufferLeft.setColorTexture(offTex);

                ViewPort viewPort = environment.getApplication().getRenderManager().createPreView(viewName, cam);
                viewPort.setClearFlags(true, true, true);
                viewPort.setBackgroundColor(ColorRGBA.Black);

                Iterator<Spatial> spatialIter = environment.getApplication().getViewPort().getScenes().iterator();
                while (spatialIter.hasNext()) {
                    viewPort.attachScene(spatialIter.next());
                }

                //set viewport to render to offscreen framebuffer
                viewPort.setOutputFrameBuffer(offBufferLeft);
                return viewPort;
            } else {
                throw new IllegalStateException("This VR environment is not attached to any application.");
            }
        } else {
            throw new IllegalStateException("This VR view manager is not attached to any VR environment.");
        }
    }
}