3 * Copyright (C) 2008 Stuart Buchanan
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation; either version 2 of the
8 * License, or (at your option) any later version.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
23 # include <simgear_config.h>
31 #include <boost/tuple/tuple_comparison.hpp>
34 #include <osg/Geometry>
36 #include <osg/MatrixTransform>
38 #include <osg/NodeVisitor>
40 #include <osgDB/ReadFile>
41 #include <osgDB/FileUtils>
43 #include <simgear/debug/logstream.hxx>
44 #include <simgear/math/sg_random.h>
45 #include <simgear/misc/sg_path.hxx>
46 #include <simgear/scene/material/Effect.hxx>
47 #include <simgear/scene/material/EffectGeode.hxx>
48 #include <simgear/props/props.hxx>
49 #include <simgear/scene/util/QuadTreeBuilder.hxx>
50 #include <simgear/scene/util/RenderConstants.hxx>
51 #include <simgear/scene/util/StateAttributeFactory.hxx>
52 #include <simgear/structure/OSGUtils.hxx>
54 #include "ShaderGeometry.hxx"
55 #include "TreeBin.hxx"
57 #define SG_TREE_QUAD_TREE_DEPTH 3
58 #define SG_TREE_FADE_OUT_LEVELS 10
65 // Tree instance scheme:
66 // vertex - local position of quad vertex.
67 // normal - x y scaling, z number of varieties
68 // fog coord - rotation
69 // color - xyz of tree quad origin, replicated 4 times.
71 // The tree quad is rendered twice, with different rotations, to
72 // create the crossed tree geometry.
74 struct TreesBoundingBoxCallback : public Drawable::ComputeBoundingBoxCallback
76 TreesBoundingBoxCallback() {}
77 TreesBoundingBoxCallback(const TreesBoundingBoxCallback&, const CopyOp&) {}
78 META_Object(simgear, TreesBoundingBoxCallback);
79 virtual BoundingBox computeBound(const Drawable&) const;
83 TreesBoundingBoxCallback::computeBound(const Drawable& drawable) const
86 const Geometry* geom = static_cast<const Geometry*>(&drawable);
87 const Vec3Array* v = static_cast<const Vec3Array*>(geom->getVertexArray());
88 const Vec3Array* pos = static_cast<const Vec3Array*>(geom->getColorArray());
89 const Vec3Array* params
90 = static_cast<const Vec3Array*>(geom->getNormalArray());
92 = static_cast<const FloatArray*>(geom->getFogCoordArray());
93 float w = (*params)[0].x();
94 float h = (*params)[0].y();
95 Geometry::PrimitiveSetList primSets = geom->getPrimitiveSetList();
96 FloatArray::const_iterator rotitr = rot->begin();
97 for (Geometry::PrimitiveSetList::const_iterator psitr = primSets.begin(),
98 psend = primSets.end();
101 Matrixd trnsfrm = (Matrixd::scale(w, w, h)
102 * Matrixd::rotate(*rotitr, Vec3(0.0f, 0.0f, 1.0f)));
103 DrawArrays* da = static_cast<DrawArrays*>(psitr->get());
104 GLint psFirst = da->getFirst();
105 GLint psEndVert = psFirst + da->getCount();
106 for (GLint i = psFirst;i < psEndVert; ++i) {
116 Geometry* makeSharedTreeGeometry(int numQuads)
118 // generate a repeatable random seed
120 mt_init(&seed, unsigned(123));
122 osg::Vec3Array* v = new osg::Vec3Array;
123 osg::Vec2Array* t = new osg::Vec2Array;
124 v->reserve(numQuads * 4);
125 t->reserve(numQuads * 4);
126 for (int i = 0; i < numQuads; ++i) {
127 // Apply a random scaling factor and texture index.
128 float h = (mt_rand(&seed) + mt_rand(&seed)) / 2.0f + 0.5f;
130 v->push_back(Vec3(0.0f, -cw, 0.0f));
131 v->push_back(Vec3(0.0f, cw, 0.0f));
132 v->push_back(Vec3(0.0f, cw, h));
133 v->push_back(Vec3(0.0f,-cw, h));
134 // The texture coordinate range is not the entire coordinate
135 // space, as the texture has a number of different trees on
136 // it. Here we assign random coordinates and let the shader
137 // choose the variety.
138 // Height isn't quite 0.25 to allow for UV map bleeding when
139 // mipmaps are generated.
140 float variety = mt_rand(&seed);
141 t->push_back(Vec2(variety, 0.0f));
142 t->push_back(Vec2(variety + 1.0f, 0.0f));
143 t->push_back(Vec2(variety + 1.0f, 0.246f));
144 t->push_back(Vec2(variety, 0.246f));
146 Geometry* result = new Geometry;
147 result->setVertexArray(v);
148 result->setTexCoordArray(0, t);
149 result->setComputeBoundingBoxCallback(new TreesBoundingBoxCallback);
150 result->setUseDisplayList(false);
154 ref_ptr<Geometry> sharedTreeGeometry;
156 Geometry* createTreeGeometry(float width, float height, int varieties)
158 if (!sharedTreeGeometry)
159 sharedTreeGeometry = makeSharedTreeGeometry(1600);
160 Geometry* quadGeom = simgear::clone(sharedTreeGeometry.get(),
161 CopyOp::SHALLOW_COPY);
162 Vec3Array* params = new Vec3Array;
163 params->push_back(Vec3(width, height, (float)varieties));
164 quadGeom->setNormalArray(params);
165 quadGeom->setNormalBinding(Geometry::BIND_OVERALL);
167 quadGeom->setColorArray(new Vec3Array);
168 quadGeom->setColorBinding(Geometry::BIND_PER_VERTEX);
169 FloatArray* rotation = new FloatArray(2);
170 (*rotation)[0] = 0.0;
171 (*rotation)[1] = PI_2;
172 quadGeom->setFogCoordArray(rotation);
173 quadGeom->setFogCoordBinding(Geometry::BIND_PER_PRIMITIVE_SET);
174 // The primitive sets render the same geometry, but the second
175 // will rotated 90 degrees by the vertex shader, which uses the
176 // fog coordinate as a rotation.
177 for (int i = 0; i < 2; ++i)
178 quadGeom->addPrimitiveSet(new DrawArrays(PrimitiveSet::QUADS));
182 EffectGeode* createTreeGeode(float width, float height, int varieties)
184 EffectGeode* result = new EffectGeode;
185 result->addDrawable(createTreeGeometry(width, height, varieties));
189 void addTreeToLeafGeode(Geode* geode, const SGVec3f& p)
192 unsigned int numDrawables = geode->getNumDrawables();
194 = static_cast<Geometry*>(geode->getDrawable(numDrawables - 1));
195 Vec3Array* posArray = static_cast<Vec3Array*>(geom->getColorArray());
197 >= static_cast<Vec3Array*>(geom->getVertexArray())->size()) {
198 Vec3Array* paramsArray
199 = static_cast<Vec3Array*>(geom->getNormalArray());
200 Vec3 params = (*paramsArray)[0];
201 geom = createTreeGeometry(params.x(), params.y(), params.z());
202 posArray = static_cast<Vec3Array*>(geom->getColorArray());
203 geode->addDrawable(geom);
205 posArray->insert(posArray->end(), 4, pos);
206 size_t numVerts = posArray->size();
207 for (int i = 0; i < 2; ++i) {
209 = static_cast<DrawArrays*>(geom->getPrimitiveSet(i));
210 primSet->setCount(numVerts);
214 typedef std::map<std::string, osg::observer_ptr<Effect> > EffectMap;
216 static EffectMap treeEffectMap;
218 // Helper classes for creating the quad tree
223 MakeTreesLeaf(float range, int varieties, float width, float height,
225 _range(range), _varieties(varieties),
226 _width(width), _height(height), _effect(effect) {}
228 MakeTreesLeaf(const MakeTreesLeaf& rhs) :
230 _varieties(rhs._varieties), _width(rhs._width), _height(rhs._height),
234 LOD* operator() () const
236 LOD* result = new LOD;
238 // Create a series of LOD nodes so trees cover decreases slightly
239 // gradually with distance from _range to 2*_range
240 for (float i = 0.0; i < SG_TREE_FADE_OUT_LEVELS; i++)
242 EffectGeode* geode = createTreeGeode(_width, _height, _varieties);
243 geode->setEffect(_effect.get());
244 result->addChild(geode, 0, _range * (1.0 + i / (SG_TREE_FADE_OUT_LEVELS - 1.0)));
252 ref_ptr<Effect> _effect;
255 struct AddTreesLeafObject
257 void operator() (LOD* lod, const TreeBin::Tree& tree) const
259 Geode* geode = static_cast<Geode*>(lod->getChild(int(tree.position.x() * 10.0f) % lod->getNumChildren()));
260 addTreeToLeafGeode(geode, tree.position);
266 Vec3 operator() (const TreeBin::Tree& tree) const
268 return toOsg(tree.position);
272 typedef QuadTreeBuilder<LOD*, TreeBin::Tree, MakeTreesLeaf, AddTreesLeafObject,
273 GetTreeCoord> ShaderGeometryQuadtree;
276 struct TreeTransformer
278 TreeTransformer(Matrix& mat_) : mat(mat_) {}
279 TreeBin::Tree operator()(const TreeBin::Tree& tree) const
281 Vec3 pos = toOsg(tree.position);
282 return TreeBin::Tree(toSG(pos * mat));
287 // We may end up with a quadtree with many empty leaves. One might say
288 // that we should avoid constructing the leaves in the first place,
289 // but this node visitor tries to clean up after the fact.
291 struct QuadTreeCleaner : public osg::NodeVisitor
293 QuadTreeCleaner() : NodeVisitor(NodeVisitor::TRAVERSE_ALL_CHILDREN)
298 for (int i = lod.getNumChildren() - 1; i >= 0; --i) {
299 EffectGeode* geode = dynamic_cast<EffectGeode*>(lod.getChild(i));
302 bool geodeEmpty = true;
303 for (unsigned j = 0; j < geode->getNumDrawables(); ++j) {
304 const Geometry* geom = dynamic_cast<Geometry*>(geode->getDrawable(j));
309 for (unsigned k = 0; k < geom->getNumPrimitiveSets(); k++) {
310 const PrimitiveSet* ps = geom->getPrimitiveSet(k);
311 if (ps->getNumIndices() > 0) {
318 lod.removeChildren(i, 1);
323 // This actually returns a MatrixTransform node. If we rotate the whole
324 // forest into the local Z-up coordinate system we can reuse the
325 // primitive tree geometry for all the forests of the same type.
327 osg::Group* createForest(SGTreeBinList& forestList, const osg::Matrix& transform,
328 const SGReaderWriterOptions* options)
330 Matrix transInv = Matrix::inverse(transform);
332 // Set up some shared structures.
333 ref_ptr<Group> group;
334 MatrixTransform* mt = new MatrixTransform(transform);
336 SGTreeBinList::iterator i;
338 for (i = forestList.begin(); i != forestList.end(); ++i) {
339 TreeBin* forest = *i;
341 ref_ptr<Effect> effect;
342 EffectMap::iterator iter = treeEffectMap.find(forest->texture);
344 if ((iter == treeEffectMap.end())||
345 (!iter->second.lock(effect)))
347 SGPropertyNode_ptr effectProp = new SGPropertyNode;
348 makeChild(effectProp, "inherits-from")->setStringValue("Effects/tree");
349 SGPropertyNode* params = makeChild(effectProp, "parameters");
351 params->getChild("texture", 0, true)->getChild("image", 0, true)
352 ->setStringValue(forest->texture);
353 effect = makeEffect(effectProp, true, options);
354 if (iter == treeEffectMap.end())
355 treeEffectMap.insert(EffectMap::value_type(forest->texture, effect));
357 iter->second = effect; // update existing, but empty observer
360 // Now, create a quadtree for the forest.
361 ShaderGeometryQuadtree
362 quadtree(GetTreeCoord(), AddTreesLeafObject(),
363 SG_TREE_QUAD_TREE_DEPTH,
364 MakeTreesLeaf(forest->range, forest->texture_varieties,
365 forest->width, forest->height, effect));
366 // Transform tree positions from the "geocentric" positions we
367 // get from the scenery polys into the local Z-up coordinate
369 std::vector<TreeBin::Tree> rotatedTrees;
370 rotatedTrees.reserve(forest->_trees.size());
371 std::transform(forest->_trees.begin(), forest->_trees.end(),
372 std::back_inserter(rotatedTrees),
373 TreeTransformer(transInv));
374 quadtree.buildQuadTree(rotatedTrees.begin(), rotatedTrees.end());
375 group = quadtree.getRoot();
377 for (size_t i = 0; i < group->getNumChildren(); ++i)
378 mt->addChild(group->getChild(i));
384 QuadTreeCleaner cleaner;