first commit

2022-10-20 20:29:11 +08:00
commit 4d531f8044
3238 changed files with 1387862 additions and 0 deletions
--- a/3rdparty/osgXR/src/Mirror.cpp
+++ b/3rdparty/osgXR/src/Mirror.cpp
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: LGPL-2.1-only
+// Copyright (C) 2021 James Hogan <james@albanarts.com>
+
+#include <osgXR/Manager>
+#include <osgXR/Mirror>
+
+#include "XRState.h"
+
+#include <osg/PolygonMode>
+
+using namespace osgXR;
+
+Mirror::Mirror(Manager *manager, osg::Camera *camera) :
+    _manager(manager),
+    _camera(camera),
+    _mirrorSettings(manager->_getSettings()->getMirrorSettings())
+{
+}
+
+Mirror::~Mirror()
+{
+}
+
+void Mirror::_init()
+{
+    _camera->setAllowEventFocus(false);
+    _camera->setViewMatrix(osg::Matrix::identity());
+    _camera->setProjectionMatrix(osg::Matrix::ortho2D(0, 1, 0, 1));
+
+    // Find the mirror settings
+    MirrorSettings *mirrorSettings = &_mirrorSettings;
+    // but fall back to the manager's mirror settings
+    if (mirrorSettings->getMirrorMode() == MirrorSettings::MIRROR_AUTOMATIC)
+        mirrorSettings = &_manager->_getSettings()->getMirrorSettings();
+    switch (mirrorSettings->getMirrorMode())
+    {
+    case MirrorSettings::MIRROR_NONE:
+        // Draw nothing, but still clear the viewport
+        _camera->setClearMask(GL_COLOR_BUFFER_BIT);
+        break;
+    case MirrorSettings::MIRROR_AUTOMATIC:
+        // Fall-through: Default to MIRROR_SINGLE
+    case MirrorSettings::MIRROR_SINGLE:
+        {
+            int viewIndex = mirrorSettings->getMirrorViewIndex();
+            if (viewIndex < 0)
+                viewIndex = 0;
+            setupQuad(viewIndex, 0.0f, 1.0f);
+        }
+        break;
+    case MirrorSettings::MIRROR_LEFT_RIGHT:
+        for (unsigned int viewIndex = 0; viewIndex < 2; ++viewIndex)
+            setupQuad(viewIndex, 0.5f * viewIndex, 0.5f);
+        break;
+    }
+}
+
+namespace {
+
+class MirrorPreDrawCallback : public osg::Camera::DrawCallback
+{
+    public:
+
+        MirrorPreDrawCallback(osg::ref_ptr<XRState> xrState,
+                              osg::ref_ptr<osg::StateSet> stateSet,
+                              unsigned int viewIndex) :
+            _xrState(xrState),
+            _stateSet(stateSet),
+            _viewIndex(viewIndex)
+        {
+        }
+
+        void operator()(osg::RenderInfo& renderInfo) const override
+        {
+            const osg::FrameStamp *stamp = renderInfo.getState()->getFrameStamp();
+            _stateSet->setTextureAttributeAndModes(0,
+                                _xrState->getViewTexture(_viewIndex, stamp));
+        }
+
+    protected:
+
+        osg::observer_ptr<XRState> _xrState;
+        osg::ref_ptr<osg::StateSet> _stateSet;
+        unsigned int _viewIndex;
+};
+
+class MirrorPostDrawCallback : public osg::Camera::DrawCallback
+{
+    public:
+
+        MirrorPostDrawCallback(osg::ref_ptr<osg::StateSet> stateSet) :
+            _stateSet(stateSet)
+        {
+        }
+
+        void operator()(osg::RenderInfo& renderInfo) const override
+        {
+            _stateSet->removeTextureAttribute(0, osg::StateAttribute::Type::TEXTURE);
+        }
+
+    protected:
+
+        osg::ref_ptr<osg::StateSet> _stateSet;
+};
+
+}
+
+void Mirror::setupQuad(unsigned int viewIndex,
+                       float x, float w)
+{
+    XRState *xrState = _manager->_getXrState();
+
+    if (viewIndex >= xrState->getViewCount())
+        return;
+
+    // Build an always-visible quad to draw the view texture on
+    osg::ref_ptr<osg::Geode> quad = new osg::Geode;
+    quad->setCullingActive(false);
+
+    XRState::TextureRect rect = xrState->getViewTextureRect(viewIndex);
+    quad->addDrawable(osg::createTexturedQuadGeometry(
+                                  osg::Vec3(x,    0.0f,  0.0f),
+                                  osg::Vec3(w,    0.0f,  0.0f),
+                                  osg::Vec3(0.0f, 1.0f,  0.0f),
+                                  rect.x, rect.y,
+                                  rect.x + rect.width, rect.y + rect.height));
+
+    osg::ref_ptr<osg::StateSet> state = quad->getOrCreateStateSet();
+    int forceOff = osg::StateAttribute::OFF | osg::StateAttribute::PROTECTED;
+    int forceOn = osg::StateAttribute::ON | osg::StateAttribute::PROTECTED;
+    state->setMode(GL_LIGHTING, forceOff);
+    state->setMode(GL_DEPTH_TEST, forceOff);
+    state->setMode(GL_FRAMEBUFFER_SRGB, forceOn);
+
+    _camera->addChild(quad);
+
+    // Set a callback so we can switch the texture to the active swapchain image
+    _camera->addPreDrawCallback(new MirrorPreDrawCallback(_manager->_getXrState(),
+                                                          state, viewIndex));
+    _camera->addPostDrawCallback(new MirrorPostDrawCallback(state));
+}