Files
OpenSceneGraph/src/osgShadow/ShadowTexture.cpp
Robert Osfield c569b8a1f3 Restoring Roger's original 2.0 factor as on review the later orthographic projection code
doesn't require the position to be far out from the center to simulate an infinite light.
2008-10-07 15:19:48 +00:00

259 lines
9.1 KiB
C++

/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* OpenSceneGraph Public License for more details.
*/
#include <osgShadow/ShadowTexture>
#include <osgShadow/ShadowedScene>
#include <osg/Notify>
#include <osg/ComputeBoundsVisitor>
#include <osg/io_utils>
using namespace osgShadow;
ShadowTexture::ShadowTexture():
_textureUnit(1)
{
}
ShadowTexture::ShadowTexture(const ShadowTexture& copy, const osg::CopyOp& copyop):
ShadowTechnique(copy,copyop),
_textureUnit(copy._textureUnit)
{
}
void ShadowTexture::setTextureUnit(unsigned int unit)
{
_textureUnit = unit;
}
void ShadowTexture::init()
{
if (!_shadowedScene) return;
unsigned int tex_width = 512;
unsigned int tex_height = 512;
_texture = new osg::Texture2D;
_texture->setTextureSize(tex_width, tex_height);
_texture->setInternalFormat(GL_RGB);
_texture->setFilter(osg::Texture2D::MIN_FILTER,osg::Texture2D::LINEAR);
_texture->setFilter(osg::Texture2D::MAG_FILTER,osg::Texture2D::LINEAR);
_texture->setWrap(osg::Texture2D::WRAP_S,osg::Texture2D::CLAMP_TO_BORDER);
_texture->setWrap(osg::Texture2D::WRAP_T,osg::Texture2D::CLAMP_TO_BORDER);
_texture->setBorderColor(osg::Vec4(1.0f,1.0f,1.0f,1.0f));
// set up the render to texture camera.
{
// create the camera
_camera = new osg::Camera;
_camera->setClearColor(osg::Vec4(1.0f,1.0f,1.0f,1.0f));
_camera->setCullCallback(new CameraCullCallback(this));
// set viewport
_camera->setViewport(0,0,tex_width,tex_height);
// set the camera to render before the main camera.
_camera->setRenderOrder(osg::Camera::PRE_RENDER);
// tell the camera to use OpenGL frame buffer object where supported.
_camera->setRenderTargetImplementation(osg::Camera::FRAME_BUFFER_OBJECT);
//_camera->setRenderTargetImplementation(osg::Camera::SEPERATE_WINDOW);
// attach the texture and use it as the color buffer.
_camera->attach(osg::Camera::COLOR_BUFFER, _texture.get());
_material = new osg::Material;
_material->setAmbient(osg::Material::FRONT_AND_BACK,osg::Vec4(0.0f,0.0f,0.0f,1.0f));
_material->setDiffuse(osg::Material::FRONT_AND_BACK,osg::Vec4(0.0f,0.0f,0.0f,1.0f));
_material->setEmission(osg::Material::FRONT_AND_BACK,osg::Vec4(0.0f,0.0f,0.0f,1.0f));
_material->setShininess(osg::Material::FRONT_AND_BACK,0.0f);
osg::StateSet* stateset = _camera->getOrCreateStateSet();
stateset->setAttribute(_material.get(),osg::StateAttribute::OVERRIDE);
}
{
_stateset = new osg::StateSet;
_stateset->setTextureAttributeAndModes(_textureUnit,_texture.get(),osg::StateAttribute::ON);
_stateset->setTextureMode(_textureUnit,GL_TEXTURE_GEN_S,osg::StateAttribute::ON);
_stateset->setTextureMode(_textureUnit,GL_TEXTURE_GEN_T,osg::StateAttribute::ON);
_stateset->setTextureMode(_textureUnit,GL_TEXTURE_GEN_R,osg::StateAttribute::ON);
_stateset->setTextureMode(_textureUnit,GL_TEXTURE_GEN_Q,osg::StateAttribute::ON);
_texgen = new osg::TexGen;
}
_dirty = false;
}
void ShadowTexture::update(osg::NodeVisitor& nv)
{
_shadowedScene->osg::Group::traverse(nv);
}
void ShadowTexture::cull(osgUtil::CullVisitor& cv)
{
// record the traversal mask on entry so we can reapply it later.
unsigned int traversalMask = cv.getTraversalMask();
osgUtil::RenderStage* orig_rs = cv.getRenderStage();
// do traversal of shadow casting scene which does not need to be decorated by the shadow texture
{
cv.setTraversalMask( traversalMask &
getShadowedScene()->getCastsShadowTraversalMask() );
_shadowedScene->osg::Group::traverse(cv);
}
// do traversal of shadow receiving scene which does need to be decorated by the shadow texture
{
cv.pushStateSet(_stateset.get());
cv.setTraversalMask( traversalMask &
getShadowedScene()->getReceivesShadowTraversalMask() );
_shadowedScene->osg::Group::traverse(cv);
cv.popStateSet();
}
// need to compute view frustum for RTT camera.
// 1) get the light position
// 2) get the center and extents of the view frustum
const osg::Light* selectLight = 0;
osg::Vec4 lightpos;
osgUtil::PositionalStateContainer::AttrMatrixList& aml = orig_rs->getPositionalStateContainer()->getAttrMatrixList();
for(osgUtil::PositionalStateContainer::AttrMatrixList::iterator itr = aml.begin();
itr != aml.end();
++itr)
{
const osg::Light* light = dynamic_cast<const osg::Light*>(itr->first.get());
if (light)
{
osg::RefMatrix* matrix = itr->second.get();
if (matrix) lightpos = light->getPosition() * (*matrix);
else lightpos = light->getPosition();
selectLight = light;
}
}
osg::Matrix eyeToWorld;
eyeToWorld.invert(*cv.getModelViewMatrix());
lightpos = lightpos * eyeToWorld;
if (selectLight)
{
// get the bounds of the model.
osg::ComputeBoundsVisitor cbbv(osg::NodeVisitor::TRAVERSE_ACTIVE_CHILDREN);
cbbv.setTraversalMask(getShadowedScene()->getCastsShadowTraversalMask());
_shadowedScene->osg::Group::traverse(cbbv);
osg::BoundingBox bb = cbbv.getBoundingBox();
if (lightpos[3]!=0.0)
{
osg::Vec3 position(lightpos.x(), lightpos.y(), lightpos.z());
float centerDistance = (position-bb.center()).length();
float znear = centerDistance-bb.radius();
float zfar = centerDistance+bb.radius();
float zNearRatio = 0.001f;
if (znear<zfar*zNearRatio) znear = zfar*zNearRatio;
float top = (bb.radius()/centerDistance)*znear;
float right = top;
_camera->setReferenceFrame(osg::Camera::ABSOLUTE_RF);
_camera->setProjectionMatrixAsFrustum(-right,right,-top,top,znear,zfar);
_camera->setViewMatrixAsLookAt(position,bb.center(),osg::Vec3(0.0f,1.0f,0.0f));
// compute the matrix which takes a vertex from local coords into tex coords
// will use this later to specify osg::TexGen..
osg::Matrix MVPT = _camera->getViewMatrix() *
_camera->getProjectionMatrix() *
osg::Matrix::translate(1.0,1.0,1.0) *
osg::Matrix::scale(0.5f,0.5f,0.5f);
_texgen->setMode(osg::TexGen::EYE_LINEAR);
_texgen->setPlanesFromMatrix(MVPT);
}
else
{
// make an orthographic projection
osg::Vec3 lightDir(lightpos.x(), lightpos.y(), lightpos.z());
lightDir.normalize();
// set the position far away along the light direction
osg::Vec3 position = bb.center() + lightDir * bb.radius() * 2.0;
float centerDistance = (position-bb.center()).length();
float znear = centerDistance-bb.radius();
float zfar = centerDistance+bb.radius();
float zNearRatio = 0.001f;
if (znear<zfar*zNearRatio) znear = zfar*zNearRatio;
float top = bb.radius();
float right = top;
_camera->setReferenceFrame(osg::Camera::ABSOLUTE_RF);
_camera->setProjectionMatrixAsOrtho(-right, right, -top, top, znear, zfar);
_camera->setViewMatrixAsLookAt(position,bb.center(),osg::Vec3(0.0f,1.0f,0.0f));
// compute the matrix which takes a vertex from local coords into tex coords
// will use this later to specify osg::TexGen..
osg::Matrix MVPT = _camera->getViewMatrix() *
_camera->getProjectionMatrix() *
osg::Matrix::translate(1.0,1.0,1.0) *
osg::Matrix::scale(0.5f,0.5f,0.5f);
_texgen->setMode(osg::TexGen::EYE_LINEAR);
_texgen->setPlanesFromMatrix(MVPT);
}
cv.setTraversalMask( traversalMask &
getShadowedScene()->getCastsShadowTraversalMask() );
// do RTT camera traversal
_camera->accept(cv);
orig_rs->getPositionalStateContainer()->addPositionedTextureAttribute(_textureUnit, cv.getModelViewMatrix(), _texgen.get());
}
// reapply the original traversal mask
cv.setTraversalMask( traversalMask );
}
void ShadowTexture::cleanSceneGraph()
{
}