OpenSceneGraph/examples/osgmultiviewOVR/MultiviewOVR.cpp
2020-12-29 13:31:15 +00:00

383 lines
15 KiB
C++

#include "MultiviewOVR.h"
#include <osgViewer/Renderer>
#include <osgViewer/View>
#include <osgViewer/GraphicsWindow>
#include <osg/io_utils>
#include <osg/Texture2DArray>
#include <osg/TextureRectangle>
#include <osg/Texture1D>
#include <osg/Texture2D>
#include <osg/TexMat>
#include <osg/Stencil>
#include <osg/PolygonStipple>
#include <osg/ValueObject>
#include <osg/DisplaySettings>
#include <osgDB/ReadFile>
#include <osgDB/WriteFile>
using namespace osgViewer;
struct CustomIntialFrustumCallback : public osg::CullSettings::InitialFrustumCallback
{
std::vector<osg::Matrixd> projectionOffsets;
std::vector<osg::Matrixd> viewOffsets;
bool applyBB = true;
osg::BoundingBoxd bb;
void toggle()
{
applyBB = !applyBB;
}
void computeClipSpaceBound(osg::Camera& camera)
{
osg::Matrixd pmv = camera.getProjectionMatrix() * camera.getViewMatrix();
size_t numOffsets = std::min(projectionOffsets.size(), viewOffsets.size());
std::vector<osg::Vec3d> world_vertices;
world_vertices.reserve(numOffsets*8);
for(size_t i=0; i<numOffsets; ++i)
{
osg::Matrixd proj = projectionOffsets[i] * camera.getProjectionMatrix();
osg::Matrixd view = viewOffsets[i] * camera.getViewMatrix();
osg::Matrix clipToWorld;
clipToWorld.invert(proj * view);
world_vertices.push_back(osg::Vec3d(-1.0, -1.0, -1.0) * clipToWorld);
world_vertices.push_back(osg::Vec3d(1.0, -1.0, -1.0) * clipToWorld);
world_vertices.push_back(osg::Vec3d(1.0, 1.0, -1.0) * clipToWorld);
world_vertices.push_back(osg::Vec3d(-1.0, 1.0, -1.0) * clipToWorld);
world_vertices.push_back(osg::Vec3d(-1.0, -1.0, 1.0) * clipToWorld);
world_vertices.push_back(osg::Vec3d(1.0, -1.0, 1.0) * clipToWorld);
world_vertices.push_back(osg::Vec3d(1.0, 1.0, 1.0) * clipToWorld);
world_vertices.push_back(osg::Vec3d(-1.0, 1.0, 1.0) * clipToWorld);
// project local clip space into world coords
// project world coords back into master clipspace
}
osg::Matrix worldToclip = camera.getProjectionMatrix() * camera.getViewMatrix();
for(auto& v : world_vertices)
{
bb.expandBy(v * worldToclip);
}
}
virtual void setInitialFrustum(osg::CullStack& cullStack, osg::Polytope& frustum) const
{
osg::CullSettings::CullingMode cullingMode = cullStack.getCullingMode();
if (applyBB)
{
frustum.setToBoundingBox(bb, ((cullingMode&osg::CullSettings::NEAR_PLANE_CULLING)!=0),((cullingMode&osg::CullSettings::FAR_PLANE_CULLING)!=0));
}
else
{
frustum.setToUnitFrustum(((cullingMode&osg::CullSettings::NEAR_PLANE_CULLING)!=0),((cullingMode&osg::CullSettings::FAR_PLANE_CULLING)!=0));
}
}
};
class ToggleFrustumHandler : public osgGA::GUIEventHandler
{
public:
ToggleFrustumHandler(CustomIntialFrustumCallback* callback) :
cifc(callback) {}
osg::ref_ptr<CustomIntialFrustumCallback> cifc;
bool handle(const osgGA::GUIEventAdapter& ea,osgGA::GUIActionAdapter&)
{
if (ea.getHandled()) return false;
switch(ea.getEventType())
{
case(osgGA::GUIEventAdapter::KEYUP):
{
if (ea.getKey()=='c')
{
cifc->toggle();
return true;
}
break;
}
default:
return false;
}
return false;
}
};
osg::ref_ptr<osg::Node> MultiviewOVR::createStereoMesh(const osg::Vec3& origin, const osg::Vec3& widthVector, const osg::Vec3& heightVector) const
{
osg::Vec3d center(0.0,0.0,0.0);
osg::Vec3d eye(0.0,0.0,0.0);
// create the quad to visualize.
osg::Geometry* geometry = new osg::Geometry();
geometry->setSupportsDisplayList(false);
osg::DrawElementsUShort* elements = new osg::DrawElementsUShort(osg::PrimitiveSet::TRIANGLES);
osg::Vec3Array* vertices = new osg::Vec3Array;
osg::Vec3Array* texcoords = new osg::Vec3Array;
osg::Vec4Array* colors = new osg::Vec4Array;
colors->push_back(osg::Vec4(1.0, 1.0, 0.0, 1.0));
// left hand side
vertices->push_back(origin); texcoords->push_back(osg::Vec3(0.0f, 0.0f, 0.0f));
vertices->push_back(origin + widthVector*0.5f); texcoords->push_back(osg::Vec3(1.0f, 0.0f, 0.0f));
vertices->push_back(origin + widthVector*0.5f +heightVector); texcoords->push_back(osg::Vec3(1.0f, 1.0f, 0.0f));
vertices->push_back(origin + heightVector); texcoords->push_back(osg::Vec3(0.0f, 1.0f, 0.0f));
elements->push_back(0);
elements->push_back(1);
elements->push_back(2);
elements->push_back(2);
elements->push_back(3);
elements->push_back(0);
// right hand side
vertices->push_back(origin + widthVector*0.5f); texcoords->push_back(osg::Vec3(0.0f, 0.0f, 1.0f));
vertices->push_back(origin + widthVector); texcoords->push_back(osg::Vec3(1.0f, 0.0f, 1.0f));
vertices->push_back(origin + widthVector +heightVector); texcoords->push_back(osg::Vec3(1.0f, 1.0f, 1.0f));
vertices->push_back(origin + widthVector*0.5f + heightVector); texcoords->push_back(osg::Vec3(0.0f, 1.0f, 1.0f));
elements->push_back(4);
elements->push_back(5);
elements->push_back(6);
elements->push_back(6);
elements->push_back(7);
elements->push_back(4);
geometry->setVertexArray(vertices);
geometry->setColorArray(colors, osg::Array::BIND_OVERALL);
geometry->setTexCoordArray(0, texcoords);
geometry->addPrimitiveSet(elements);
return geometry;
}
void MultiviewOVR::configure(osgViewer::View& view) const
{
osg::GraphicsContext::WindowingSystemInterface* wsi = osg::GraphicsContext::getWindowingSystemInterface();
if (!wsi)
{
OSG_NOTICE<<"Error, no WindowSystemInterface available, cannot create windows."<<std::endl;
return;
}
osg::DisplaySettings* displaySettings = getActiveDisplaySetting(view);
osg::GraphicsContext::ScreenIdentifier si;
si.readDISPLAY();
// displayNum has not been set so reset it to 0.
if (si.displayNum<0) si.displayNum = 0;
si.screenNum = _screenNum;
unsigned int width, height;
wsi->getScreenResolution(si, width, height);
osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;
traits->hostName = si.hostName;
traits->displayNum = si.displayNum;
traits->screenNum = si.screenNum;
traits->x = 0;
traits->y = 0;
traits->width = width;
traits->height = height;
traits->windowDecoration = false;
traits->doubleBuffer = true;
traits->sharedContext = 0;
osg::ref_ptr<osg::GraphicsContext> gc = osg::GraphicsContext::createGraphicsContext(traits.get());
if (!gc)
{
OSG_NOTICE<<"GraphicsWindow has not been created successfully."<<std::endl;
return;
}
int tex_width = width;
int tex_height = height;
int camera_width = tex_width;
int camera_height = tex_height;
osg::Texture2DArray* color_texture = new osg::Texture2DArray;
color_texture->setTextureSize(tex_width, tex_height, 2);
color_texture->setInternalFormat(GL_RGBA);
color_texture->setFilter(osg::Texture::MIN_FILTER,osg::Texture::LINEAR);
color_texture->setFilter(osg::Texture::MAG_FILTER,osg::Texture::LINEAR);
color_texture->setWrap(osg::Texture::WRAP_S,osg::Texture::CLAMP_TO_EDGE);
color_texture->setWrap(osg::Texture::WRAP_T,osg::Texture::CLAMP_TO_EDGE);
color_texture->setWrap(osg::Texture::WRAP_R,osg::Texture::CLAMP_TO_EDGE);
osg::Texture2DArray* depth_texture = new osg::Texture2DArray;
depth_texture->setTextureSize(tex_width, tex_height, 2);
depth_texture->setInternalFormat(GL_DEPTH_COMPONENT);
depth_texture->setFilter(osg::Texture::MIN_FILTER,osg::Texture::LINEAR);
depth_texture->setFilter(osg::Texture::MAG_FILTER,osg::Texture::LINEAR);
depth_texture->setWrap(osg::Texture::WRAP_S,osg::Texture::CLAMP_TO_EDGE);
depth_texture->setWrap(osg::Texture::WRAP_T,osg::Texture::CLAMP_TO_EDGE);
depth_texture->setWrap(osg::Texture::WRAP_R,osg::Texture::CLAMP_TO_EDGE);
osg::Camera::RenderTargetImplementation renderTargetImplementation = osg::Camera::FRAME_BUFFER_OBJECT;
GLenum buffer = GL_FRONT;
// left/right eye multiviewOVR camera
{
// GL_OVR_multiview2 extensions requires modern versions of GLSL without fixed function fallback
gc->getState()->setUseModelViewAndProjectionUniforms(true);
gc->getState()->setUseVertexAttributeAliasing(true);
//osg::DisplaySettings::instance()->setShaderHint(osg::DisplaySettings::SHADER_GL3);
osg::ref_ptr<osg::Camera> camera = new osg::Camera;
camera->setName("multview eye camera");
camera->setGraphicsContext(gc.get());
camera->setViewport(new osg::Viewport(0,0,camera_width, camera_height));
camera->setDrawBuffer(buffer);
camera->setReadBuffer(buffer);
camera->setAllowEventFocus(false);
osg::ref_ptr<CustomIntialFrustumCallback> ifc = new CustomIntialFrustumCallback;
view.addEventHandler(new ToggleFrustumHandler(ifc.get()));
// assign custom frustum callback
camera->setInitialFrustumCallback(ifc.get());
// tell the camera to use OpenGL frame buffer object where supported.
camera->setRenderTargetImplementation(renderTargetImplementation);
// attach the texture and use it as the color buffer, specify that the face is controlled by the multiview extension
camera->attach(osg::Camera::COLOR_BUFFER, color_texture, 0, osg::Camera::FACE_CONTROLLED_BY_MULTIVIEW_SHADER);
camera->attach(osg::Camera::DEPTH_BUFFER, depth_texture, 0, osg::Camera::FACE_CONTROLLED_BY_MULTIVIEW_SHADER);
view.addSlave(camera.get(), osg::Matrixd(), osg::Matrixd());
osg::StateSet* stateset = camera->getOrCreateStateSet();
{
// set up the projection and view matrix uniforms
ifc->projectionOffsets.push_back(displaySettings->computeLeftEyeProjectionImplementation(osg::Matrixd()));
ifc->viewOffsets.push_back(displaySettings->computeLeftEyeViewImplementation(osg::Matrixd()));
ifc->projectionOffsets.push_back(displaySettings->computeRightEyeProjectionImplementation(osg::Matrixd()));
ifc->viewOffsets.push_back(displaySettings->computeRightEyeViewImplementation(osg::Matrixd()));
ifc->computeClipSpaceBound(*camera);
osg::ref_ptr<osg::Uniform> ovr_viewMatrix_uniform = new osg::Uniform(osg::Uniform::FLOAT_MAT4, "ovr_viewMatrix", ifc->projectionOffsets.size());
osg::ref_ptr<osg::Uniform> ovr_projectionMatrix_uniform = new osg::Uniform(osg::Uniform::FLOAT_MAT4, "ovr_projectionMatrix", ifc->viewOffsets.size());
stateset->addUniform(ovr_viewMatrix_uniform);
stateset->addUniform(ovr_projectionMatrix_uniform);
for(size_t i=0; i<ifc->projectionOffsets.size(); ++i)
{
ovr_projectionMatrix_uniform->setElement(i, ifc->projectionOffsets[i]);
}
for(size_t i=0; i<ifc->viewOffsets.size(); ++i)
{
ovr_viewMatrix_uniform->setElement(i, ifc->viewOffsets[i]);
}
// set up the shaders
osg::ref_ptr<osg::Program> program = new osg::Program();
stateset->setAttribute(program.get(), osg::StateAttribute::ON);
std::string vsFileName("multiviewOVR.vert");
std::string fsFileName("multiviewOVR.frag");
osg::ref_ptr<osg::Shader> vertexShader = osgDB::readRefShaderFile( osg::Shader::VERTEX, vsFileName) ;
if (vertexShader.get()) program->addShader( vertexShader.get() );
osg::ref_ptr<osg::Shader> fragmentShader = osgDB::readRefShaderFile( osg::Shader::FRAGMENT, fsFileName) ;
if (fragmentShader.get()) program->addShader( fragmentShader.get() );
}
}
view.getCamera()->setProjectionMatrixAsPerspective(90.0f, 1.0, 1, 1000.0);
// distortion correction set up.
{
osg::ref_ptr<osg::Node> mesh = createStereoMesh(osg::Vec3(0.0f,0.0f,0.0f), osg::Vec3(width,0.0f,0.0f), osg::Vec3(0.0f,height,0.0f));
// new we need to add the texture to the mesh, we do so by creating a
// StateSet to contain the Texture StateAttribute.
osg::StateSet* stateset = mesh->getOrCreateStateSet();
stateset->setTextureAttribute(0, color_texture, osg::StateAttribute::ON);
stateset->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
{
osg::ref_ptr<osg::Program> program = new osg::Program();
stateset->setAttribute(program.get(), osg::StateAttribute::ON);
std::string vsFileName("standard.vert");
std::string fsFileName("standard.frag");
osg::ref_ptr<osg::Shader> vertexShader = osgDB::readRefShaderFile( osg::Shader::VERTEX, vsFileName) ;
if (vertexShader.get()) program->addShader( vertexShader.get() );
osg::ref_ptr<osg::Shader> fragmentShader = osgDB::readRefShaderFile( osg::Shader::FRAGMENT, fsFileName) ;
if (fragmentShader.get()) program->addShader( fragmentShader.get() );
}
osg::ref_ptr<osg::Camera> camera = new osg::Camera;
camera->setGraphicsContext(gc.get());
camera->setClearMask(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT );
camera->setClearColor( osg::Vec4(0.0,0.0,0.0,1.0) );
camera->setViewport(new osg::Viewport(0, 0, width, height));
GLenum window_buffer = traits->doubleBuffer ? GL_BACK : GL_FRONT;
camera->setDrawBuffer(window_buffer);
camera->setReadBuffer(window_buffer);
camera->setReferenceFrame(osg::Camera::ABSOLUTE_RF);
camera->setAllowEventFocus(true);
camera->setInheritanceMask(camera->getInheritanceMask() & ~osg::CullSettings::CLEAR_COLOR & ~osg::CullSettings::COMPUTE_NEAR_FAR_MODE);
//camera->setComputeNearFarMode(osg::CullSettings::DO_NOT_COMPUTE_NEAR_FAR);
camera->setProjectionMatrixAsOrtho2D(0,width,0,height);
camera->setViewMatrix(osg::Matrix::identity());
// add subgraph to render
camera->addChild(mesh.get());
camera->setName("DistortionCorrectionCamera");
osgDB::writeNodeFile(*mesh, "mesh.osgt");
view.addSlave(camera.get(), osg::Matrixd(), osg::Matrixd(), false);
}
view.getCamera()->setNearFarRatio(0.0001f);
if (view.getLightingMode()==osg::View::HEADLIGHT)
{
// set a local light source for headlight to ensure that lighting is consistent across sides of cube.
view.getLight()->setPosition(osg::Vec4(0.0f,0.0f,0.0f,1.0f));
}
}