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>
39 #include <osgDB/ReadFile>
40 #include <osgDB/FileUtils>
42 #include <simgear/debug/logstream.hxx>
43 #include <simgear/math/sg_random.h>
44 #include <simgear/misc/sg_path.hxx>
45 #include <simgear/scene/material/Effect.hxx>
46 #include <simgear/scene/material/EffectGeode.hxx>
47 #include <simgear/props/props.hxx>
48 #include <simgear/scene/util/QuadTreeBuilder.hxx>
49 #include <simgear/scene/util/RenderConstants.hxx>
50 #include <simgear/scene/util/StateAttributeFactory.hxx>
51 #include <simgear/structure/OSGUtils.hxx>
53 #include "ShaderGeometry.hxx"
54 #include "TreeBin.hxx"
56 #define SG_TREE_QUAD_TREE_DEPTH 3
57 #define SG_TREE_FADE_OUT_LEVELS 10
64 // Tree instance scheme:
65 // vertex - local position of quad vertex.
66 // normal - x y scaling, z number of varieties
67 // fog coord - rotation
68 // color - xyz of tree quad origin, replicated 4 times.
70 // The tree quad is rendered twice, with different rotations, to
71 // create the crossed tree geometry.
73 struct TreesBoundingBoxCallback : public Drawable::ComputeBoundingBoxCallback
75 TreesBoundingBoxCallback() {}
76 TreesBoundingBoxCallback(const TreesBoundingBoxCallback&, const CopyOp&) {}
77 META_Object(simgear, TreesBoundingBoxCallback);
78 virtual BoundingBox computeBound(const Drawable&) const;
82 TreesBoundingBoxCallback::computeBound(const Drawable& drawable) const
85 const Geometry* geom = static_cast<const Geometry*>(&drawable);
86 const Vec3Array* v = static_cast<const Vec3Array*>(geom->getVertexArray());
87 const Vec3Array* pos = static_cast<const Vec3Array*>(geom->getColorArray());
88 const Vec3Array* params
89 = static_cast<const Vec3Array*>(geom->getNormalArray());
91 = static_cast<const FloatArray*>(geom->getFogCoordArray());
92 float w = (*params)[0].x();
93 float h = (*params)[0].y();
94 Geometry::PrimitiveSetList primSets = geom->getPrimitiveSetList();
95 FloatArray::const_iterator rotitr = rot->begin();
96 for (Geometry::PrimitiveSetList::const_iterator psitr = primSets.begin(),
97 psend = primSets.end();
100 Matrixd trnsfrm = (Matrixd::scale(w, w, h)
101 * Matrixd::rotate(*rotitr, Vec3(0.0f, 0.0f, 1.0f)));
102 DrawArrays* da = static_cast<DrawArrays*>(psitr->get());
103 GLint psFirst = da->getFirst();
104 GLint psEndVert = psFirst + da->getCount();
105 for (GLint i = psFirst;i < psEndVert; ++i) {
115 Geometry* makeSharedTreeGeometry(int numQuads)
117 // generate a repeatable random seed
119 mt_init(&seed, unsigned(123));
121 osg::Vec3Array* v = new osg::Vec3Array;
122 osg::Vec2Array* t = new osg::Vec2Array;
123 v->reserve(numQuads * 4);
124 t->reserve(numQuads * 4);
125 for (int i = 0; i < numQuads; ++i) {
126 // Apply a random scaling factor and texture index.
127 float h = (mt_rand(&seed) + mt_rand(&seed)) / 2.0f + 0.5f;
129 v->push_back(Vec3(0.0f, -cw, 0.0f));
130 v->push_back(Vec3(0.0f, cw, 0.0f));
131 v->push_back(Vec3(0.0f, cw, h));
132 v->push_back(Vec3(0.0f,-cw, h));
133 // The texture coordinate range is not the entire coordinate
134 // space, as the texture has a number of different trees on
135 // it. Here we assign random coordinates and let the shader
136 // choose the variety.
137 float variety = mt_rand(&seed);
138 t->push_back(Vec2(variety, 0.0f));
139 t->push_back(Vec2(variety + 1.0f, 0.0f));
140 t->push_back(Vec2(variety + 1.0f, 1.0f));
141 t->push_back(Vec2(variety, 1.0f));
143 Geometry* result = new Geometry;
144 result->setVertexArray(v);
145 result->setTexCoordArray(0, t);
146 result->setComputeBoundingBoxCallback(new TreesBoundingBoxCallback);
147 result->setUseDisplayList(false);
151 ref_ptr<Geometry> sharedTreeGeometry;
153 Geometry* createTreeGeometry(float width, float height, int varieties)
155 if (!sharedTreeGeometry)
156 sharedTreeGeometry = makeSharedTreeGeometry(1600);
157 Geometry* quadGeom = simgear::clone(sharedTreeGeometry.get(),
158 CopyOp::SHALLOW_COPY);
159 Vec3Array* params = new Vec3Array;
160 params->push_back(Vec3(width, height, (float)varieties));
161 quadGeom->setNormalArray(params);
162 quadGeom->setNormalBinding(Geometry::BIND_OVERALL);
164 quadGeom->setColorArray(new Vec3Array);
165 quadGeom->setColorBinding(Geometry::BIND_PER_VERTEX);
166 FloatArray* rotation = new FloatArray(2);
167 (*rotation)[0] = 0.0;
168 (*rotation)[1] = PI_2;
169 quadGeom->setFogCoordArray(rotation);
170 quadGeom->setFogCoordBinding(Geometry::BIND_PER_PRIMITIVE_SET);
171 // The primitive sets render the same geometry, but the second
172 // will rotated 90 degrees by the vertex shader, which uses the
173 // fog coordinate as a rotation.
174 for (int i = 0; i < 2; ++i)
175 quadGeom->addPrimitiveSet(new DrawArrays(PrimitiveSet::QUADS));
179 EffectGeode* createTreeGeode(float width, float height, int varieties)
181 EffectGeode* result = new EffectGeode;
182 result->addDrawable(createTreeGeometry(width, height, varieties));
186 void addTreeToLeafGeode(Geode* geode, const SGVec3f& p)
189 unsigned int numDrawables = geode->getNumDrawables();
191 = static_cast<Geometry*>(geode->getDrawable(numDrawables - 1));
192 Vec3Array* posArray = static_cast<Vec3Array*>(geom->getColorArray());
194 >= static_cast<Vec3Array*>(geom->getVertexArray())->size()) {
195 Vec3Array* paramsArray
196 = static_cast<Vec3Array*>(geom->getNormalArray());
197 Vec3 params = (*paramsArray)[0];
198 geom = createTreeGeometry(params.x(), params.y(), params.z());
199 posArray = static_cast<Vec3Array*>(geom->getColorArray());
200 geode->addDrawable(geom);
202 posArray->insert(posArray->end(), 4, pos);
203 size_t numVerts = posArray->size();
204 for (int i = 0; i < 2; ++i) {
206 = static_cast<DrawArrays*>(geom->getPrimitiveSet(i));
207 primSet->setCount(numVerts);
211 typedef std::map<std::string, osg::ref_ptr<Effect> > EffectMap;
213 static EffectMap treeEffectMap;
215 // Helper classes for creating the quad tree
220 MakeTreesLeaf(float range, int varieties, float width, float height,
222 _range(range), _varieties(varieties),
223 _width(width), _height(height), _effect(effect) {}
225 MakeTreesLeaf(const MakeTreesLeaf& rhs) :
227 _varieties(rhs._varieties), _width(rhs._width), _height(rhs._height),
231 LOD* operator() () const
233 LOD* result = new LOD;
235 // Create a series of LOD nodes so trees cover decreases slightly
236 // gradually with distance from _range to 2*_range
237 for (float i = 0.0; i < SG_TREE_FADE_OUT_LEVELS; i++)
239 EffectGeode* geode = createTreeGeode(_width, _height, _varieties);
240 geode->setEffect(_effect.get());
241 result->addChild(geode, 0, _range * (1.0 + i / (SG_TREE_FADE_OUT_LEVELS - 1.0)));
249 ref_ptr<Effect> _effect;
252 struct AddTreesLeafObject
254 void operator() (LOD* lod, const TreeBin::Tree& tree) const
256 Geode* geode = static_cast<Geode*>(lod->getChild(int(tree.position.x() * 10.0f) % lod->getNumChildren()));
257 addTreeToLeafGeode(geode, tree.position);
263 Vec3 operator() (const TreeBin::Tree& tree) const
265 return toOsg(tree.position);
269 typedef QuadTreeBuilder<LOD*, TreeBin::Tree, MakeTreesLeaf, AddTreesLeafObject,
270 GetTreeCoord> ShaderGeometryQuadtree;
273 struct TreeTransformer
275 TreeTransformer(Matrix& mat_) : mat(mat_) {}
276 TreeBin::Tree operator()(const TreeBin::Tree& tree) const
278 Vec3 pos = toOsg(tree.position);
279 return TreeBin::Tree(toSG(pos * mat));
284 // This actually returns a MatrixTransform node. If we rotate the whole
285 // forest into the local Z-up coordinate system we can reuse the
286 // primitive tree geometry for all the forests of the same type.
288 osg::Group* createForest(SGTreeBinList& forestList, const osg::Matrix& transform)
290 Matrix transInv = Matrix::inverse(transform);
292 // Set up some shared structures.
293 ref_ptr<Group> group;
294 MatrixTransform* mt = new MatrixTransform(transform);
296 SGTreeBinList::iterator i;
298 for (i = forestList.begin(); i != forestList.end(); ++i) {
299 TreeBin* forest = *i;
302 EffectMap::iterator iter = treeEffectMap.find(forest->texture);
303 if (iter == treeEffectMap.end()) {
304 SGPropertyNode_ptr effectProp = new SGPropertyNode;
305 makeChild(effectProp, "inherits-from")->setStringValue("Effects/tree");
306 SGPropertyNode* params = makeChild(effectProp, "parameters");
308 params->getChild("texture", 0, true)->getChild("image", 0, true)
309 ->setStringValue(forest->texture);
310 effect = makeEffect(effectProp, true);
311 treeEffectMap.insert(EffectMap::value_type(forest->texture, effect));
313 effect = iter->second.get();
316 // Now, create a quadtree for the forest.
317 ShaderGeometryQuadtree
318 quadtree(GetTreeCoord(), AddTreesLeafObject(),
319 SG_TREE_QUAD_TREE_DEPTH,
320 MakeTreesLeaf(forest->range, forest->texture_varieties,
321 forest->width, forest->height, effect));
322 // Transform tree positions from the "geocentric" positions we
323 // get from the scenery polys into the local Z-up coordinate
325 std::vector<TreeBin::Tree> rotatedTrees;
326 rotatedTrees.reserve(forest->_trees.size());
327 std::transform(forest->_trees.begin(), forest->_trees.end(),
328 std::back_inserter(rotatedTrees),
329 TreeTransformer(transInv));
330 quadtree.buildQuadTree(rotatedTrees.begin(), rotatedTrees.end());
331 group = quadtree.getRoot();
333 for (size_t i = 0; i < group->getNumChildren(); ++i)
334 mt->addChild(group->getChild(i));