+++ /dev/null
-// Shadow volume class
-//
-// Written by Harald JOHNSEN, started June 2005.
-//
-// Copyright (C) 2005 Harald JOHNSEN - hjohnsen@evc.net
-//
-// This program is free software; you can redistribute it and/or
-// modify it under the terms of the GNU General Public License as
-// published by the Free Software Foundation; either version 2 of the
-// License, or (at your option) any later version.
-//
-// This program 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 GNU
-// General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program; if not, write to the Free Software
-// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
-//
-//
-
-#ifdef HAVE_CONFIG_H
-# include <simgear_config.h>
-#endif
-
-#include <plib/sg.h>
-#include <simgear/debug/logstream.hxx>
-#include <simgear/screen/extensions.hxx>
-#include <simgear/scene/model/animation.hxx>
-#include <simgear/scene/model/model.hxx>
-#include <simgear/environment/visual_enviro.hxx>
-#include <osg/GLU>
-
-#include "shadowvolume.hxx"
-
-/*
- geometry and edge list
- - traverse object graph until leaf to get geometry
- - what about transform and selection ?
- - use sub objects rather then objects
- - get local transform and selection
- - range anim : ssgRangeSelector ( min, max ) => ssgSelector ( true/false )
- => selection [0..n], kids [0..n]
- - select/timed anim : ssgSelector ( true/false )
- => isSelected( nkid )
- - spin/rotate/trans/scale/... : ssgTransform ( matrix )
- => getNetTransform
- - on new object :
- - for one object branch
- - for each leaf
- - save geometry
- - save address in cache
- - when rendering object
- - for each leaf
- - getNetTransform + object global rotation (ac) => transform for light position
- - go up in tree and check isSelected( self )
- - generate connectivity each time the geometry change
- => using local light so connectivity never changes
- - generate active edge list when :
- - light moves
- - subpart moves (animation code)
- - ac rotate
- => cache rotation matrix and generate edge list only if something change
- => even if it changes, no need to do that every frame
-
- - static objects have static edge list if light does not move
-
- shadowing a scene
- - render full scene as normal
- - render occluder in stencil buffer with their shadow volumes
- - apply stencil to framebuffer (darkens shadowed parts)
-
- shadows using the alpha buffer
- http://wwwvis.informatik.uni-stuttgart.de/~roettger/html/Pages/shadows.html
-*/
-
-// TODO
-// - shadow for objects
-// * aircraft
-// * tile objects (from .stg)
-// - ai objects
-// - random objects => tie shadow geometry to lib objects and reuse them
-// - zfail if camera inside shadow
-// - queue geometry work if lot of objects
-// * add a render property on/off (for aircraft, for scene objects, for ai)
-// * add a render property in rendering dialog
-// * filter : halo, light, shadow, disc, disk, flame, (exhaust), noshadow
-
-static int statSilhouette=0;
-static int statGeom=0;
-static int statObj=0;
-
-static SGShadowVolume *states;
-static glBlendEquationProc glBlendEquationPtr = NULL;
-#define GL_MIN_EXT 0x8007
-#define GL_MAX_EXT 0x8008
-
-
-SGShadowVolume::ShadowCaster::ShadowCaster( int _num_tri, ssgBranch * _geometry_leaf ) :
- geometry_leaf ( _geometry_leaf ),
- scenery_object ( 0 ),
- first_select ( 0 ),
- frameNumber ( 0 ),
- indices ( 0 ),
- numTriangles ( 0 ),
- vertices ( 0 ),
- lastSilhouetteIndicesCount ( 0 )
-{
- int num_tri = _num_tri;
- numTriangles = num_tri;
- triangles = new triData[ num_tri ];
- indices = new int[1 + num_tri * 3];
- vertices = new sgVec4[1 + num_tri * 3];
- silhouetteEdgeIndices = new GLushort[(1+num_tri) * 3*3];
- indices [ num_tri * 3 ] = num_tri * 3;
- sgSetVec3(last_lightpos, 0.0, 0.0, 0.0);
- statGeom ++;
-
- ssgBranch *branch = (ssgBranch *) _geometry_leaf;
- while( branch && branch->getNumParents() > 0 ) {
- if( branch->isAKindOf(ssgTypeSelector())) {
- first_select = branch;
- break;
- }
- if( sgCheckAnimationBranch( (ssgEntity *) branch ) )
- if( ((SGAnimation *) branch->getUserData())->get_animation_type() == 1) {
- first_select = branch;
- break;
- }
- branch = branch->getParent(0);
- }
-}
-
-void SGShadowVolume::ShadowCaster::addLeaf( int & tri_idx, int & ind_idx, ssgLeaf *geometry_leaf ) {
- int num_tri = geometry_leaf->getNumTriangles();
- for(int i = 0; i < num_tri ; i ++ ) {
- short v1, v2, v3;
- sgVec3 a, b, c;
- geometry_leaf->getTriangle( i, &v1, &v2, &v3 );
- sgCopyVec3(a, geometry_leaf->getVertex(v1));
- sgCopyVec3(b, geometry_leaf->getVertex(v2));
- sgCopyVec3(c, geometry_leaf->getVertex(v3));
-
- int p = tri_idx;
- sgMakePlane ( triangles[p].planeEquations, a, b, c );
- sgCopyVec3(vertices[ind_idx + v1], a);
- sgCopyVec3(vertices[ind_idx + v2], b);
- sgCopyVec3(vertices[ind_idx + v3], c);
- vertices[ind_idx + v1][SG_W] = 1.0f;
- vertices[ind_idx + v2][SG_W] = 1.0f;
- vertices[ind_idx + v3][SG_W] = 1.0f;
- indices[p*3] = ind_idx + v1;
- indices[p*3+1] = ind_idx + v2;
- indices[p*3+2] = ind_idx + v3;
-
- tri_idx++;
- }
- if( num_tri == 0 )
- return;
- isTranslucent |= geometry_leaf->isTranslucent() ? true : false;
- int num_ind = geometry_leaf->getNumVertices();
- ind_idx += num_ind;
-}
-
-SGShadowVolume::ShadowCaster::~ShadowCaster() {
- delete [] indices ;
- delete [] vertices ;
- delete [] triangles;
- delete [] silhouetteEdgeIndices;
-}
-
-
-
-bool SGShadowVolume::ShadowCaster::sameVertex(int edge1, int edge2) {
- if( edge1 == edge2)
- return true;
- sgVec3 delta_v;
- sgSubVec3( delta_v, vertices[edge1], vertices[edge2]);
- if( delta_v[SG_X] != 0.0) return false;
- if( delta_v[SG_Y] != 0.0) return false;
- if( delta_v[SG_Z] != 0.0) return false;
- return true;
-}
-
-
-//Calculate neighbour faces for each edge
-// caution, this is O(n2)
-void SGShadowVolume::ShadowCaster::SetConnectivity(void)
-{
- int edgeCount = 0;
-
- //set the neighbour indices to be -1
- for(int ii=0; ii<numTriangles; ++ii)
- triangles[ii].neighbourIndices[0] =
- triangles[ii].neighbourIndices[1] =
- triangles[ii].neighbourIndices[2] = -1;
-
- //loop through triangles
- for(int i=0; i<numTriangles-1; ++i)
- {
- //loop through edges on the first triangle
- for(int edgeI=0; edgeI<3; ++edgeI)
- {
- //continue if this edge already has a neighbour set
- if(triangles[i].neighbourIndices[ edgeI ]!=-1)
- continue;
-
- //get the vertex indices on each edge
- int edgeI1=indices[i*3+edgeI];
- int edgeI2=indices[i*3+(edgeI == 2 ? 0 : edgeI+1)];
-
- //loop through triangles with greater indices than this one
- for(int j=i+1; j<numTriangles; ++j)
- {
- //loop through edges on triangle j
- for(int edgeJ=0; edgeJ<3; ++edgeJ)
- {
- //continue if this edge already has a neighbour set
- if(triangles[j].neighbourIndices[ edgeJ ]!=-1) {
- continue;
- }
- //get the vertex indices on each edge
- int edgeJ1=indices[j*3+edgeJ];
- int edgeJ2=indices[j*3+(edgeJ == 2 ? 0 : edgeJ+1)];
-
- //if these are the same (possibly reversed order), these faces are neighbours
-#if 0
- //no, we only use reverse order because same order means that
- //the triangle is wrongly oriented and that will cause shadow artifact
- if( sameVertex(edgeI1, edgeJ1) && sameVertex(edgeI2, edgeJ2) ) {
- // can happens with 'bad' geometry
-// printf("flipped triangle detected...check your model\n");
- continue;
- }
-#endif
- if( sameVertex(edgeI1, edgeJ2) && sameVertex(edgeI2, edgeJ1) )
- {
- int edgeI3=indices[i*3+(edgeI == 0 ? 2 : edgeI-1)];
- int edgeJ3=indices[j*3+(edgeJ == 0 ? 2 : edgeJ-1)];
- if( sameVertex(edgeI3, edgeJ3) ) {
- // can happens with 'bad' geometry
-// printf("duplicated tri...check your model\n");
- // exit loop
- break;
- }
- triangles[i].neighbourIndices[edgeI]=j;
- triangles[j].neighbourIndices[edgeJ]=i;
- edgeCount ++;
- // exit loop
- j = numTriangles;
- break;
- }
- }
- }
- }
- }
-// printf("submodel has %d triangles and %d shared edges\n", numTriangles, edgeCount);
-}
-
-//calculate silhouette edges
-void SGShadowVolume::ShadowCaster::CalculateSilhouetteEdges(sgVec3 lightPosition)
-{
- //Calculate which faces face the light
- for(int i=0; i<numTriangles; ++i)
- {
- if( sgDistToPlaneVec3 ( triangles[i].planeEquations, lightPosition ) > 0.0 )
- triangles[i].isFacingLight=true;
- else
- triangles[i].isFacingLight=false;
- }
-
- //loop through faces
- int iEdgeIndices = 0;
- sgVec4 farCap = {-lightPosition[SG_X], -lightPosition[SG_Y], -lightPosition[SG_Z], 1.0f};
- sgCopyVec4( vertices[ numTriangles*3 ], farCap );
-
- for(int t=0; t < numTriangles; t++) {
- int v = t * 3;
- //if this face is not facing the light, not a silhouette edge
- if(!triangles[t].isFacingLight)
- {
- triangles[t].isSilhouetteEdge[0]=false;
- triangles[t].isSilhouetteEdge[1]=false;
- triangles[t].isSilhouetteEdge[2]=false;
- continue;
- }
- //loop through edges
- for(int j = 0 ; j < 3 ; j++) {
- //this face is facing the light
- //if the neighbouring face is not facing the light, or there is no neighbouring face,
- //then this is a silhouette edge
- if(triangles[t].neighbourIndices[j]==-1 ||
- !triangles[triangles[t].neighbourIndices[j]].isFacingLight ) {
- triangles[t].isSilhouetteEdge[j]=true;
- silhouetteEdgeIndices[ iEdgeIndices++ ] = indices[v+(j == 2 ? 0 : j+1)];
- silhouetteEdgeIndices[ iEdgeIndices++ ] = indices[v+j];
- silhouetteEdgeIndices[ iEdgeIndices++ ] = numTriangles * 3;
- }
- else
- triangles[t].isSilhouetteEdge[j]=false;
- }
- }
- lastSilhouetteIndicesCount = iEdgeIndices;
-}
-
-void SGShadowVolume::ShadowCaster::DrawInfiniteShadowVolume(sgVec3 lightPosition, bool drawCaps)
-{
- glEnableClientState ( GL_VERTEX_ARRAY ) ;
- glVertexPointer ( 4, GL_FLOAT, 0, vertices ) ;
- glDrawElements ( GL_TRIANGLES, lastSilhouetteIndicesCount, GL_UNSIGNED_SHORT, silhouetteEdgeIndices ) ;
-
- //Draw caps if required
- if(drawCaps)
- {
- glBegin(GL_TRIANGLES);
- {
- for(int i=0; i<numTriangles; ++i)
- {
- if(triangles[i].isFacingLight) {
- int v = i*3;
- glVertex3fv( vertices[indices[v+0]] );
- glVertex3fv( vertices[indices[v+1]] );
- glVertex3fv( vertices[indices[v+2]] );
- }
- }
- }
- glEnd();
- }
-}
-
-
-void SGShadowVolume::ShadowCaster::getNetTransform ( ssgBranch * branch, sgMat4 xform )
-{
- // one less matmult...
- bool first = true;
- while( branch && branch != lib_object ) {
- if( branch->isA(ssgTypeTransform()) ) {
- sgMat4 transform;
- if( first ) {
- ((ssgTransform *) branch)->getTransform( xform );
- first = false;
- } else {
- ((ssgTransform *) branch)->getTransform(transform);
- sgPostMultMat4 ( xform, transform ) ;
- }
- }
- branch = branch->getParent( 0 );
- }
- if( first )
- sgMakeIdentMat4 ( xform ) ;
-}
-
-// check the value of <select> and <range> animation
-// wich have been computed during the rendering
-bool SGShadowVolume::ShadowCaster::isSelected ( ssgBranch * branch, float dist ) {
- while( branch && branch != lib_object) {
- if( sgCheckAnimationBranch( (ssgEntity *) branch ) ) {
- if( ((SGAnimation *) branch->getUserData())->get_animation_type() == 1)
- if( ((SGShadowAnimation *) branch->getUserData())->get_condition_value() )
- return false;
- }
- // recompute range check since the value in the branch is shared by multiple objects
- // we can only have the last value
- if( branch->isA(ssgTypeRangeSelector()) )
- if( dist >= ((ssgRangeSelector *) branch)->getRange(1) ||
- dist < ((ssgRangeSelector *) branch)->getRange(0))
- return false;
- if( branch->isA(ssgTypeSelector()) )
- if( !((ssgSelector *) branch)->isSelected(0) )
- return false;
- branch = branch->getParent(0);
- }
- return true;
-}
-/*
- trans ----- personality ---- shared object
- perso1 *-----
- \
- *--------* shared object
- /
- perso2 *-----
-*/
-void SGShadowVolume::ShadowCaster::computeShadows(sgMat4 rotation, sgMat4 rotation_translation,
- OccluderType occluder_type) {
-
- // check the select and range ssgSelector node
- // object can't cast shadow if it is not visible
- sgVec4 trans;
- sgCopyVec4( trans, rotation_translation[3] );
- sgAddVec4( trans, states->CameraViewM[3] );
- float dist = sgLengthVec3( trans );
-
- if( first_select && ! isSelected( first_select, dist) )
- return;
-
- // get the transformations : this comes from animation code for example
- // or static transf
- sgMat4 transf;
- sgVec3 lightPos;
- int deltaFrame = occluder_type == SGShadowVolume::occluderTypeAircraft ? 0 : 9;
- if( states->frameNumber - frameNumber > deltaFrame) {
- sgMat4 transform ;
- sgMat4 invTransform;
- getNetTransform( (ssgBranch *) geometry_leaf, transform );
- sgCopyMat4( last_transform, transform );
- sgPostMultMat4( transform, rotation );
- sgTransposeNegateMat4 ( invTransform, transform );
-
- sgCopyVec3( lightPos, states->sunPos );
- sgXformPnt3( lightPos, invTransform );
-
- sgVec3 lightPosNorm;
- sgNormaliseVec3( lightPosNorm, lightPos );
- float deltaPos = sgAbs(lightPosNorm[0] - last_lightpos[0]) +
- sgAbs(lightPosNorm[1] - last_lightpos[1]) +
- sgAbs(lightPosNorm[2] - last_lightpos[2]);
- // if the geometry has rotated/moved enought then
- // we need to recompute the silhouette
- // but this computation does not need to be done each frame
- if( deltaPos > 0.0 ) {
- CalculateSilhouetteEdges( lightPos );
- sgCopyVec3( last_lightpos, lightPosNorm );
- frameNumber = states->frameNumber ;
- statSilhouette ++;
- }
- }
- sgCopyMat4( transf, last_transform );
- sgPostMultMat4( transf, rotation_translation );
- glLoadMatrixf ( (float *) states->CameraViewM ) ;
- glMultMatrixf( (float *) transf );
-
- if( states->shadowsDebug_enabled )
- {
- glStencilFunc(GL_ALWAYS, 0, ~0);
- glDisable( GL_CULL_FACE );
- glDisable( GL_DEPTH_TEST );
- glDisable(GL_STENCIL_TEST);
- glColorMask(1, 1, 1, 1);
- glColor4f(0.0, 0.0, 1.0, 1.0);
- glBegin(GL_LINES);
- for(int i=0; i<numTriangles; ++i)
- {
- if(!triangles[i].isFacingLight)
- continue;
- int v = i*3;
- //Loop through edges on this face
- sgVec3 vertex1, vertex2, vertex3;
- sgCopyVec3(vertex1, vertices[indices[v+0]]);
- sgCopyVec3(vertex2, vertices[indices[v+1]]);
- sgCopyVec3(vertex3, vertices[indices[v+2]]);
-
- if(triangles[i].isSilhouetteEdge[0]) {
- glVertex3fv(vertex2);
- glVertex3fv(vertex1);
- }
- if(triangles[i].isSilhouetteEdge[1]) {
- glVertex3fv(vertex2);
- glVertex3fv(vertex3);
- }
- if(triangles[i].isSilhouetteEdge[2]) {
- glVertex3fv(vertex3);
- glVertex3fv(vertex1);
- }
- }
- glEnd();
- glColorMask(0, 0, 0, 0);
- glEnable( GL_CULL_FACE );
- glEnable( GL_DEPTH_TEST );
- glEnable(GL_STENCIL_TEST);
- }
-
-
- // TODO:compute intersection with near clip plane...
- bool needZFail=false;
-
- // GL_INCR_WRAP_EXT, GL_DECR_WRAP_EXT
-
- if(needZFail)
- {
- //Increment stencil buffer for back face depth fail
- glStencilFunc(GL_ALWAYS, 0, ~0);
- glStencilOp(GL_KEEP, GL_INCR, GL_KEEP);
- glCullFace(GL_FRONT);
-
- DrawInfiniteShadowVolume( lightPos, true);
-
- //Decrement stencil buffer for front face depth fail
- glStencilOp(GL_KEEP, GL_DECR, GL_KEEP);
- glCullFace(GL_BACK);
-
- DrawInfiniteShadowVolume( lightPos, true);
- }
- else //using zpass
- {
- //Increment stencil buffer for front face depth pass
- if( states->use_alpha ) {
- glBlendEquationPtr( GL_FUNC_ADD );
- glBlendFunc( GL_ONE, GL_ONE );
- glColor4ub(1, 1, 1, 16);
- } else {
- glColor4f(1.0f, 1.0f, 0.0f, 0.5f);
- glStencilFunc(GL_ALWAYS, 0, ~0);
- glStencilOp(GL_KEEP, GL_KEEP, GL_INCR);
- }
- glCullFace(GL_BACK);
-
- DrawInfiniteShadowVolume( lightPos, states->shadowsAC_transp_enabled & isTranslucent);
-
- //Decrement stencil buffer for back face depth pass
- if( states->use_alpha ) {
- glBlendEquationPtr( GL_FUNC_REVERSE_SUBTRACT );
- glBlendFunc( GL_ONE, GL_ONE );
- glColor4ub(1, 1, 1, 16);
- } else {
- glStencilOp(GL_KEEP, GL_KEEP, GL_DECR);
- }
- glCullFace(GL_FRONT);
-
- DrawInfiniteShadowVolume( lightPos, states->shadowsAC_transp_enabled & isTranslucent);
- }
-}
-
-
-void SGShadowVolume::SceneryObject::computeShadows(void) {
-
- // compute intersection with view frustum
- // use pending_object (pointer on obj transform) & tile transform
- // to get position
- if( !scenery_object ) {
- if( states->frameNumber - states->lastTraverseTreeFrame > 5 ) {
- find_trans();
- if( scenery_object )
- traverseTree( pending_object );
- states->lastTraverseTreeFrame = states->frameNumber;
- }
- return;
- }
- sgMat4 rotation, rotation_translation;
- scenery_object->getNetTransform ( rotation_translation );
- // split placement offset into rotation and offset
- // rotation from model inside world
- // we are not interested in translation since the light is very far away
- // without translation we reduce the frequency of updates of the silouhette
- sgCopyMat4( rotation, rotation_translation );
- sgSetVec4( rotation[3], 0, 0, 0, 1);
-
- ShadowCaster_list::iterator iShadowCaster;
- for(iShadowCaster = parts.begin() ; iShadowCaster != parts.end() ; ++iShadowCaster ) {
- (*iShadowCaster)->computeShadows(rotation, rotation_translation, occluder_type);
- }
-}
-
-static ssgCullResult cull_test ( ssgEntity *e, sgFrustum *f, sgMat4 m, int test_needed )
-{
- if ( ! test_needed )
- return SSG_INSIDE ;
-
- sgSphere tmp = *(e->getBSphere()) ;
-
- if ( tmp.isEmpty () )
- return SSG_OUTSIDE ;
-
- tmp . orthoXform ( m ) ;
- if( tmp.center[2] == 0.0 )
- return SSG_STRADDLE;
- // cull if too small on screen
- if ( tmp.radius / sgAbs(tmp.center[2]) < 1.0 / 40.0 )
- return SSG_OUTSIDE ;
-
- return (ssgCullResult) f -> contains ( &tmp ) ;
-}
-
-
-void SGShadowVolume::cull ( ssgBranch *b, sgFrustum *f, sgMat4 m, int test_needed )
-{
- int cull_result = cull_test ( (ssgEntity *) b, f, m, test_needed ) ;
-
- if ( cull_result == SSG_OUTSIDE )
- return ;
- if( b->isA( ssgTypeTransform() ) ) {
-
- SceneryObject_map::iterator iSceneryObject = sceneryObjects.find( b );
- if( iSceneryObject != sceneryObjects.end() ) {
- SceneryObject *an_occluder = iSceneryObject->second;
- if( shadowsTO_enabled && (an_occluder->occluder_type == occluderTypeTileObject) ||
- shadowsAI_enabled && (an_occluder->occluder_type == occluderTypeAI ) ||
- shadowsAC_enabled && (an_occluder->occluder_type == occluderTypeAircraft ) )
- an_occluder->computeShadows();
-
- return;
- }
- sgMat4 tmp, transform ;
- sgCopyMat4 ( tmp, m ) ;
- ((ssgTransform *)b)->getTransform( transform );
- sgPreMultMat4 ( tmp, transform ) ;
- glPushMatrix () ;
- glLoadMatrixf ( (float *) tmp ) ;
- for ( ssgEntity *e = b->getKid ( 0 ) ; e != NULL ; e = b->getNextKid() )
- cull ( (ssgBranch *) e, f, tmp, cull_result != SSG_INSIDE ) ;
- glPopMatrix () ;
- } else if( b->isAKindOf( ssgTypeSelector() ) ) {
- int s = ((ssgSelector *) b)->getSelect() ;
- if( b->isA( ssgTypeRangeSelector() ) ) {
- float range = sgLengthVec3 ( m [ 3 ] ) ;
- s = (range < ((ssgRangeSelector *) b)->getRange(1) &&
- range >= ((ssgRangeSelector *) b)->getRange(0) ) ? 1 : 0;
- }
- for ( ssgEntity *e = b->getKid ( 0 ) ; e != NULL ; e = b->getNextKid(), s >>= 1 )
- if ( s & 1 )
- cull ( (ssgBranch *) e, f, m, cull_result != SSG_INSIDE ) ;
- } else if( b->isAKindOf( ssgTypeBranch() ) ) {
- char *name = b->getName();
- // quick exit for the hundreds of ground leafs
- if( name && !strcmp(name, "LocalTerrain") )
- return;
- for ( ssgEntity *e = b->getKid ( 0 ) ; e != NULL ; e = b->getNextKid() )
- if( ! e->isAKindOf( ssgTypeLeaf() ) )
- cull ( (ssgBranch *) e, f, m, cull_result != SSG_INSIDE ) ;
- }
-}
-
-/*
- 1) starting at the root of a scene object we follow all branch to find vertex leaf.
- each vertex leaf will create a shadow sub object so that the shadow casted by this
- geometry can be correctly rendered according to select or transform nodes.
- 2) models are not optimized for shadows because the geometry is cut by
- - select / transform nodes
- - material differences
- since we are not interested in the geometry material we try to merge same level
- leafs. this can divide the number of shadow sub models by a lot (reducing the cpu
- overhead for matrix computation) and at the end this will reduce the number of
- silouhette edge by a lot too.
-*/
-static bool filterLeaf(ssgLeaf *this_kid) {
- const char *leaf_name = this_kid->getName();
-/* ssgSimpleState *sst = (ssgSimpleState *) this_kid->getState();
- if( sst && sst->isTranslucent() )
- return false;*/
- if( ! leaf_name )
- return true;
- char lname[20];
- unsigned int l = 0;
- char *buff;
- for( buff = lname; *leaf_name && l < (sizeof( lname )-1); ++buff, l++ )
- *buff = tolower(*leaf_name++);
- *buff = 0;
- if( !strncmp(lname, "noshadow", 8) )
- return false;
- return true;
-}
-void SGShadowVolume::SceneryObject::traverseTree(ssgBranch *branch) {
- int num_tri = 0;
- int num_leaf = 0;
-
- if( sgCheckAnimationBranch( (ssgEntity *) branch ) ) {
- if( ((SGAnimation *) branch->getUserData())->get_animation_type() == 1)
- if( ((SGShadowAnimation *) branch->getUserData())->get_condition_value() )
- return;
- }
-
- for(int i = 0 ; i < branch->getNumKids() ; i++) {
- ssgEntity *this_kid = branch->getKid( i );
- if( this_kid->isAKindOf(ssgTypeLeaf()) ) {
- if( filterLeaf( (ssgLeaf *) this_kid ) ) {
- num_tri += ((ssgLeaf *) this_kid)->getNumTriangles();
- num_leaf ++;
- }
- } else
- traverseTree( (ssgBranch *) this_kid );
- }
- if( num_tri > 0) {
- int tri_idx = 0;
- int ind_idx = 0;
- ShadowCaster *new_part = new ShadowCaster( num_tri, branch);
- new_part->scenery_object = scenery_object;
- new_part->lib_object = lib_object;
- new_part->isTranslucent = false;
- for(int i = 0 ; i < branch->getNumKids() ; i++) {
- ssgEntity *this_kid = branch->getKid( i );
- if( this_kid->isAKindOf(ssgTypeLeaf()) ) {
- if( filterLeaf( (ssgLeaf *) this_kid ) )
- new_part->addLeaf( tri_idx, ind_idx, (ssgLeaf *) this_kid );
- }
- }
- // only do that for aircraft
- if( occluder_type != SGShadowVolume::occluderTypeAircraft )
- new_part->isTranslucent = false;
- new_part->SetConnectivity();
- parts.push_back( new_part );
- }
-}
-
-void SGShadowVolume::SceneryObject::find_trans(void) {
- ssgBranch *branch = pending_object;
- // check the existence of the root node
- while( branch && branch->getNumParents() > 0 ) {
- branch = branch->getParent(0);
- }
- // check if we are connected to the scene graph
- if( !branch->isA(ssgTypeRoot() ) )
- return;
- scenery_object = pending_object;
-}
-
-SGShadowVolume::SceneryObject::SceneryObject(ssgBranch *_scenery_object, OccluderType _occluder_type) :
- scenery_object ( 0 ),
- pending_object ( _scenery_object ),
- occluder_type ( _occluder_type )
-{
- // queue objects, don't do all the work in the first frames because of
- // massive cpu power needed
- statObj++;
- if( occluder_type == SGShadowVolume::occluderTypeAircraft )
- lib_object = _scenery_object;
- else
- lib_object = (ssgBranch *) ((ssgBranch *)_scenery_object->getKid(0))->getKid(0);
-}
-
-SGShadowVolume::SceneryObject::~SceneryObject()
-{
- ShadowCaster_list::iterator iParts;
- for(iParts = parts.begin() ; iParts != parts.end(); ++iParts ) {
- delete *iParts;
- }
- parts.clear();
-}
-
-void SGShadowVolume::computeShadows(void) {
-
- // intensity = ambient + lights
- // lights = sun_const * (sun_angle . normal)
- double dot_light = cos(sun_angle);
- // do nothing if sun is under horizon
- if( dot_light < 0.2 )
- return;
-
- //Draw shadow volumes
- glPushAttrib(GL_ALL_ATTRIB_BITS);
- glPushClientAttrib ( GL_CLIENT_VERTEX_ARRAY_BIT ) ;
- glDisableClientState ( GL_COLOR_ARRAY ) ;
- glDisableClientState ( GL_NORMAL_ARRAY ) ;
- glDisableClientState ( GL_TEXTURE_COORD_ARRAY ) ;
-
- if( use_alpha ) {
- glColorMask(0, 0, 0, 1);
- glClearColor(0.0, 0.0, 0.0, 0.0 );
- glClear(GL_COLOR_BUFFER_BIT);
- glDisable(GL_ALPHA);
- glEnable(GL_BLEND);
- } else {
- glClearStencil( 0 );
- glClear(GL_STENCIL_BUFFER_BIT);
- glColorMask(0, 0, 0, 0);
- glEnable(GL_STENCIL_TEST);
- glDisable(GL_ALPHA);
- glDisable(GL_BLEND);
- }
- glDisable( GL_LIGHTING );
- glDisable( GL_FOG );
- glEnable( GL_CULL_FACE );
-// glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
- glPolygonOffset(0.0,2.0);
-// glPolygonOffset(0.0,30.0);
- glEnable(GL_POLYGON_OFFSET_FILL);
-
- glShadeModel(GL_FLAT);
-
- glDepthMask( false );
- glEnable( GL_DEPTH_TEST );
- glDepthFunc(GL_LESS);
-
- {
- float w, h;
- sgFrustum frustum;
- sgEnviro.getFOV( w, h );
- frustum.setFOV( w, h );
- frustum.setNearFar(0.1f, 5000.0f);
- sgMat4 m;
- ssgGetModelviewMatrix( m );
- cull( ssg_root, &frustum, m, true);
- }
-
-
- glMatrixMode ( GL_PROJECTION ) ;
- glPushMatrix () ;
- glLoadIdentity () ;
- glOrtho ( -100, 100, -100, 100, -1, 1 ) ;
- glMatrixMode ( GL_MODELVIEW ) ;
- glPushMatrix () ;
- glLoadIdentity () ;
-
- glDisable(GL_DEPTH_TEST);
- glDisable(GL_CULL_FACE);
-// glBindTexture(GL_TEXTURE_2D, 0);
- glPolygonMode(GL_FRONT, GL_FILL);
- if( use_alpha ) {
- // there is a flaw in the Roettger paper, this does not work for some geometry
- // where we increment (multiply) the buffer a few times then we
- // decrement (divide) a few times. Decrementing more then once will give a
- // non shadowed parts with mask value < 0.25 because the incrementation was
- // clamped
- // Solution : don't use a start value as high as 0.25 but the smallest value
- // posible ie 1/256. This is not a general solution, a stencil buffer will
- // support 255 incrementation before clamping, the alpha mask only 7.
- // => that still does not work with our geometry so use subtractive blend
-
- // clamp mask = {0,16,32,64,...} => {0,16,16,16,...}
- glBlendEquationPtr( GL_MIN_EXT );
- glBlendFunc( GL_DST_COLOR, GL_ONE );
- glColor4ub(1, 1, 1, 16);
- glRectf(-100,-100,100,100);
- // scale mask = {0,16} => {0,64}
- glBlendEquationPtr( GL_FUNC_ADD );
- glBlendFunc( GL_DST_COLOR, GL_ONE );
- glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
- glRectf(-100,-100,100,100);
- glRectf(-100,-100,100,100);
- // negate mask => {0,64} => {255, 191}
- glBlendFunc( GL_ONE_MINUS_DST_COLOR, GL_ZERO );
- glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
- glRectf(-100,-100,100,100);
- // apply mask
- glColorMask(1, 1, 1, 1);
- glBlendFunc( GL_ZERO, GL_DST_ALPHA );
- glColor4f(1.0f, 0.5f, 0.2f, 1.0f);
- glRectf(-100,-100,100,100);
- } else {
- // now the stencil contains 0 for scenery in light and != 0 for parts in shadow
- // draw a quad covering the screen, the stencil will be the mask
- // we darken the shadowed parts
- glColorMask(1, 1, 1, 1);
- glStencilFunc(GL_NOTEQUAL, 0, ~0);
- glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
- glEnable(GL_STENCIL_TEST);
- glEnable(GL_ALPHA);
- glAlphaFunc(GL_GREATER, 0.0f);
- glEnable(GL_BLEND);
- glBlendFunc ( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA ) ;
- glColor4f(0.0, 0.0, 0.0, sgLerp(0.1, 0.3, dot_light) );
- // fixed value is better, the previous line is surely wrong
- glColor4f(0.0, 0.0, 0.0, 0.3 );
- glRectf(-100,-100,100,100);
- }
- glMatrixMode ( GL_PROJECTION ) ;
- glPopMatrix () ;
- glMatrixMode ( GL_MODELVIEW ) ;
- glPopMatrix () ;
-
- glDisable(GL_STENCIL_TEST);
- glPopClientAttrib ( ) ;
- glPopAttrib();
-}
-
-SGShadowVolume::SGShadowVolume( ssgBranch *root ) :
- shadows_enabled( false ),
- frameNumber( 0 ),
- lastTraverseTreeFrame ( 0 ),
- ssg_root( root ),
- shadows_rendered( false )
-{
- states = this;
-}
-
-SGShadowVolume::~SGShadowVolume() {
- SceneryObject_map::iterator iSceneryObject;
- for(iSceneryObject = sceneryObjects.begin() ; iSceneryObject != sceneryObjects.end(); ++iSceneryObject ) {
- delete iSceneryObject->second;
- }
- sceneryObjects.clear();
-}
-
-void SGShadowVolume::init(SGPropertyNode *sim_rendering_options) {
- shadows_enabled = true;
- sim_rendering = sim_rendering_options;
- GLint stencilBits = 0, alphaBits = 0;
- glGetIntegerv( GL_STENCIL_BITS, &stencilBits );
- glGetIntegerv( GL_ALPHA_BITS, &alphaBits );
- bool hasSubtractiveBlend = SGIsOpenGLExtensionSupported("GL_EXT_blend_subtract");
- bool hasMinMaxBlend = SGIsOpenGLExtensionSupported("GL_EXT_blend_minmax");
- if( hasSubtractiveBlend )
- glBlendEquationPtr = (glBlendEquationProc ) SGLookupFunction("glBlendEquationEXT");
- canDoAlpha = (alphaBits >= 8) && hasSubtractiveBlend && hasMinMaxBlend;
- canDoStencil = (stencilBits >= 3);
- if( !canDoStencil )
- if( canDoAlpha )
- SG_LOG(SG_ALL, SG_WARN, "SGShadowVolume:no stencil buffer, using alpha buffer");
- else
- SG_LOG(SG_ALL, SG_WARN, "SGShadowVolume:no stencil buffer and no alpha buffer");
-}
-
-void SGShadowVolume::startOfFrame(void) {
-}
-void SGShadowVolume::deleteOccluderFromTile(ssgBranch *tile) {
- SceneryObject_map::iterator iSceneryObject;
- for(iSceneryObject = sceneryObjects.begin() ; iSceneryObject != sceneryObjects.end(); ) {
- SceneryObject_map::iterator iCurrent = iSceneryObject ++;
- if( iCurrent->second->tile == tile ) {
- delete iCurrent->second;
- sceneryObjects.erase( iCurrent );
- }
- }
-}
-
-void SGShadowVolume::deleteOccluder(ssgBranch *occluder) {
- // skip first node and go to first transform (placement)
- while( occluder && !occluder->isA(ssgTypeTransform()))
- occluder = (ssgBranch *) occluder->getKid(0);
-
- // check if we allready know this object
- SceneryObject_map::iterator iSceneryObject = sceneryObjects.find( occluder );
- if( iSceneryObject != sceneryObjects.end() ) {
- delete iSceneryObject->second;
- sceneryObjects.erase( occluder );
- }
-}
-
-void SGShadowVolume::addOccluder(ssgBranch *occluder, OccluderType occluder_type, ssgBranch *tile) {
- // skip first node and go to first transform (placement)
- while( occluder && !occluder->isA(ssgTypeTransform()))
- occluder = (ssgBranch *) occluder->getKid(0);
-
- // check if we allready know this object
- SceneryObject_map::iterator iSceneryObject = sceneryObjects.find( occluder );
- if( iSceneryObject == sceneryObjects.end() ) {
-// printf("adding model %x %x\n", occluder, tile);
- SceneryObject *entry = new SceneryObject( occluder, occluder_type );
- entry->tile = tile;
- sceneryObjects[ occluder ] = entry;
- }
-
-}
-
-void SGShadowVolume::setupShadows( double lon, double lat,
- double gst, double SunRightAscension, double SunDeclination, double sunAngle) {
-
- shadowsAC_enabled = sim_rendering->getBoolValue("shadows-ac", false);
- shadowsAC_transp_enabled = sim_rendering->getBoolValue("shadows-ac-transp", false);
- shadowsAI_enabled = sim_rendering->getBoolValue("shadows-ai", false);
- shadowsTO_enabled = sim_rendering->getBoolValue("shadows-to", false);
- shadowsDebug_enabled = sim_rendering->getBoolValue("shadows-debug", false);
- shadows_enabled = shadowsAC_enabled || shadowsAI_enabled || shadowsTO_enabled;
- shadows_enabled &= canDoAlpha || canDoStencil;
- use_alpha = ((!canDoStencil) || sim_rendering->getBoolValue("shadows-alpha", false)) &&
- canDoAlpha;
-
- if( ! shadows_enabled )
- return;
-
- shadows_rendered = false;
- sun_angle = sunAngle;
- {
- sgMat4 GST, RA, DEC;
- sgVec3 axis;
-
-
- sgSetVec3( axis, 0.0, 0.0, -1.0 );
- sgMakeRotMat4( GST, (gst) * 15.0, axis );
-
- sgSetVec3( axis, 0.0, 0.0, 1.0 );
- sgMakeRotMat4( RA, (SunRightAscension * SGD_RADIANS_TO_DEGREES) - 90.0, axis );
-
- sgSetVec3( axis, 1.0, 0.0, 0.0 );
- sgMakeRotMat4( DEC, SunDeclination * SGD_RADIANS_TO_DEGREES, axis );
-
- sgMat4 TRANSFORM;
- sgMakeIdentMat4( TRANSFORM );
- sgPreMultMat4( TRANSFORM, GST );
- sgPreMultMat4( TRANSFORM, RA );
- sgPreMultMat4( TRANSFORM, DEC );
- sgSetVec3( sunPos, 0.0, 9900000.0, 0.0);
- sgXformPnt3( sunPos, TRANSFORM );
- }
-
- ssgGetModelviewMatrix( CameraViewM );
-
-}
-
-void SGShadowVolume::endOfFrame(void) {
- if( ! shadows_enabled )
- return;
- if( shadows_rendered )
- return;
- glBindTexture(GL_TEXTURE_2D, 0);
- glBindTexture(GL_TEXTURE_1D, 0);
-
- glMatrixMode(GL_MODELVIEW);
- computeShadows();
- frameNumber ++;
- shadows_rendered = true;
-}
-
-int SGShadowVolume::ACpostTravCB( ssgEntity *entity, int traversal_mask ) {
- if( states->shadowsAC_transp_enabled && (SSGTRAV_CULL & traversal_mask) )
- states->endOfFrame();
- return 0;
-}
-
projects / simgear.git / commitdiff