*
*/
+#ifdef HAVE_CONFIG_H
+# include <simgear_config.h>
+#endif
+
#include <algorithm>
+#include <vector>
#include <string>
#include <map>
-#include <osg/AlphaFunc>
-#include <osg/Billboard>
-#include <osg/BlendFunc>
+#include <boost/tuple/tuple_comparison.hpp>
+
#include <osg/Geode>
#include <osg/Geometry>
-#include <osg/Material>
#include <osg/Math>
#include <osg/MatrixTransform>
#include <osg/Matrix>
-#include <osg/StateSet>
-#include <osg/Texture2D>
-#include <osg/TexEnv>
#include <osgDB/ReadFile>
#include <osgDB/FileUtils>
+#include <simgear/debug/logstream.hxx>
+#include <simgear/math/sg_random.h>
#include <simgear/misc/sg_path.hxx>
+#include <simgear/scene/material/Effect.hxx>
+#include <simgear/scene/material/EffectGeode.hxx>
+#include <simgear/props/props.hxx>
#include <simgear/scene/util/QuadTreeBuilder.hxx>
#include <simgear/scene/util/RenderConstants.hxx>
#include <simgear/scene/util/StateAttributeFactory.hxx>
+#include <simgear/structure/OSGUtils.hxx>
#include "ShaderGeometry.hxx"
#include "TreeBin.hxx"
#define SG_TREE_QUAD_TREE_DEPTH 3
-
-// Comments from Tim Moore:
-// Some work remains for this code. Stuart's enhancement for multiple
-// textures per forest should be integrated. We should try to use one
-// ShaderGeometry for *all* the trees in the scene graph and do the
-// rotation and scale with a MatrixTransform above the trees quad
-// tree. The positions would of course have to be transformed by the
-// inverse of that transform. Also, we should investigate whether it
-// would be better to instantiate trees as polygons in a osg::Geometry
-// object instead of using the ShaderGeometry instancing technique.
+#define SG_TREE_FADE_OUT_LEVELS 10
using namespace osg;
namespace simgear
{
-osg::Geometry* createOrthQuads(float w, float h, int varieties, const osg::Matrix& rotate)
+// Tree instance scheme:
+// vertex - local position of quad vertex.
+// normal - x y scaling, z number of varieties
+// fog coord - rotation
+// color - xyz of tree quad origin, replicated 4 times.
+//
+// The tree quad is rendered twice, with different rotations, to
+// create the crossed tree geometry.
+
+struct TreesBoundingBoxCallback : public Drawable::ComputeBoundingBoxCallback
+{
+ TreesBoundingBoxCallback() {}
+ TreesBoundingBoxCallback(const TreesBoundingBoxCallback&, const CopyOp&) {}
+ META_Object(simgear, TreesBoundingBoxCallback);
+ virtual BoundingBox computeBound(const Drawable&) const;
+};
+
+BoundingBox
+TreesBoundingBoxCallback::computeBound(const Drawable& drawable) const
{
+ BoundingBox bb;
+ const Geometry* geom = static_cast<const Geometry*>(&drawable);
+ const Vec3Array* v = static_cast<const Vec3Array*>(geom->getVertexArray());
+ const Vec3Array* pos = static_cast<const Vec3Array*>(geom->getColorArray());
+ const Vec3Array* params
+ = static_cast<const Vec3Array*>(geom->getNormalArray());
+ const FloatArray* rot
+ = static_cast<const FloatArray*>(geom->getFogCoordArray());
+ float w = (*params)[0].x();
+ float h = (*params)[0].y();
+ Geometry::PrimitiveSetList primSets = geom->getPrimitiveSetList();
+ FloatArray::const_iterator rotitr = rot->begin();
+ for (Geometry::PrimitiveSetList::const_iterator psitr = primSets.begin(),
+ psend = primSets.end();
+ psitr != psend;
+ ++psitr, ++rotitr) {
+ Matrixd trnsfrm = (Matrixd::scale(w, w, h)
+ * Matrixd::rotate(*rotitr, Vec3(0.0f, 0.0f, 1.0f)));
+ DrawArrays* da = static_cast<DrawArrays*>(psitr->get());
+ GLint psFirst = da->getFirst();
+ GLint psEndVert = psFirst + da->getCount();
+ for (GLint i = psFirst;i < psEndVert; ++i) {
+ Vec3 pt = (*v)[i];
+ pt = pt * trnsfrm;
+ pt += (*pos)[i];
+ bb.expandBy(pt);
+ }
+ }
+ return bb;
+}
- //const osg::Vec3& pos = osg::Vec3(0.0f,0.0f,0.0f),
+Geometry* makeSharedTreeGeometry(int numQuads)
+{
+ // generate a repeatable random seed
+ mt seed;
+ mt_init(&seed, unsigned(123));
// set up the coords
- // Create front and back polygons so we don't need to screw around
- // with two-sided lighting in the shader.
- osg::Vec3Array& v = *(new osg::Vec3Array(8));
- osg::Vec3Array& n = *(new osg::Vec3Array(8));
- osg::Vec2Array& t = *(new osg::Vec2Array(8));
-
- float cw = w*0.5f;
-
- v[0].set(0.0f,-cw,0.0f);
- v[1].set(0.0f, cw,0.0f);
- v[2].set(0.0f, cw,h);
- v[3].set(0.0f,-cw,h);
-
- v[4].set(-cw,0.0f,0.0f);
- v[5].set( cw,0.0f,0.0f);
- v[6].set( cw,0.0f,h);
- v[7].set(-cw,0.0f,h);
-
- // The texture coordinate range is not the
- // entire coordinate space - as the texture
- // has a number of different trees on it.
- float tx = 1.0f/varieties;
-
- t[0].set(0.0f,0.0f);
- t[1].set( tx,0.0f);
- t[2].set( tx,1.0f);
- t[3].set(0.0f,1.0f);
-
- t[4].set(0.0f,0.0f);
- t[5].set( tx,0.0f);
- t[6].set( tx,1.0f);
- t[7].set(0.0f,1.0f);
-
- // For now the normal is normal to the quad. If we want to get
- // fancier and approximate a cylindrical tree or something, then
- // we would really want more geometry.
- std::fill(n.begin(), n.begin() + 4, Vec3f(1.0f, 0.0f, 0.0f));
- std::fill(n.begin() + 4, n.end(), Vec3f(0.0f, -1.0f, 0.0f));
- for (unsigned int i = 0; i < 8; i++) {
- v[i] = v[i] * rotate;
- // Should be the inverse transpose, but assume that rotate is
- // orthonormal.
- n[i] = n[i] * rotate;
+ osg::Vec3Array* v = new osg::Vec3Array;
+ osg::Vec2Array* t = new osg::Vec2Array;
+ v->reserve(numQuads * 4);
+ t->reserve(numQuads * 4);
+ for (int i = 0; i < numQuads; ++i) {
+ // Apply a random scaling factor and texture index.
+ float h = (mt_rand(&seed) + mt_rand(&seed)) / 2.0f + 0.5f;
+ float cw = h * .5;
+ v->push_back(Vec3(0.0f, -cw, 0.0f));
+ v->push_back(Vec3(0.0f, cw, 0.0f));
+ v->push_back(Vec3(0.0f, cw, h));
+ v->push_back(Vec3(0.0f,-cw, h));
+ // The texture coordinate range is not the entire coordinate
+ // space, as the texture has a number of different trees on
+ // it. Here we assign random coordinates and let the shader
+ // choose the variety.
+ float variety = mt_rand(&seed);
+ t->push_back(Vec2(variety, 0.0f));
+ t->push_back(Vec2(variety + 1.0f, 0.0f));
+ t->push_back(Vec2(variety + 1.0f, 1.0f));
+ t->push_back(Vec2(variety, 1.0f));
}
+ Geometry* result = new Geometry;
+ result->setVertexArray(v);
+ result->setTexCoordArray(0, t);
+ result->setComputeBoundingBoxCallback(new TreesBoundingBoxCallback);
+ result->setUseDisplayList(false);
+ return result;
+}
- osg::Geometry *geom = new osg::Geometry;
+ref_ptr<Geometry> sharedTreeGeometry;
- geom->setVertexArray(&v);
- geom->setTexCoordArray(0, &t);
- geom->setNormalArray(&n);
- geom->setNormalBinding(Geometry::BIND_PER_VERTEX);
- // No color for now; that's used to pass the position.
- geom->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::QUADS,0,8));
+Geometry* createTreeGeometry(float width, float height, int varieties)
+{
+ if (!sharedTreeGeometry)
+ sharedTreeGeometry = makeSharedTreeGeometry(1600);
+ Geometry* quadGeom = simgear::clone(sharedTreeGeometry.get(),
+ CopyOp::SHALLOW_COPY);
+ Vec3Array* params = new Vec3Array;
+ params->push_back(Vec3(width, height, (float)varieties));
+ quadGeom->setNormalArray(params);
+ quadGeom->setNormalBinding(Geometry::BIND_OVERALL);
+ // Positions
+ quadGeom->setColorArray(new Vec3Array);
+ quadGeom->setColorBinding(Geometry::BIND_PER_VERTEX);
+ FloatArray* rotation = new FloatArray(2);
+ (*rotation)[0] = 0.0;
+ (*rotation)[1] = PI_2;
+ quadGeom->setFogCoordArray(rotation);
+ quadGeom->setFogCoordBinding(Geometry::BIND_PER_PRIMITIVE_SET);
+ // The primitive sets render the same geometry, but the second
+ // will rotated 90 degrees by the vertex shader, which uses the
+ // fog coordinate as a rotation.
+ for (int i = 0; i < 2; ++i)
+ quadGeom->addPrimitiveSet(new DrawArrays(PrimitiveSet::QUADS));
+ return quadGeom;
+}
- return geom;
+EffectGeode* createTreeGeode(float width, float height, int varieties)
+{
+ EffectGeode* result = new EffectGeode;
+ result->addDrawable(createTreeGeometry(width, height, varieties));
+ return result;
}
- static char vertexShaderSource[] =
- "varying vec2 texcoord;\n"
- "varying float fogFactor;\n"
- "attribute float textureIndex;\n"
- "\n"
- "void main(void)\n"
- "{\n"
- " texcoord = gl_MultiTexCoord0.st + vec2(textureIndex, 0.0);\n"
- " vec3 position = gl_Vertex.xyz * gl_Color.w + gl_Color.xyz;\n"
- " gl_Position = gl_ModelViewProjectionMatrix * vec4(position,1.0);\n"
- " vec3 ecPosition = vec3(gl_ModelViewMatrix * vec4(position, 1.0));\n"
- " vec3 N = normalize(gl_NormalMatrix * gl_Normal);\n"
- " vec3 diffuse = gl_FrontMaterial.diffuse.rgb * max(0.0, dot(N, gl_LightSource[0].position.xyz));\n"
- " vec3 backDiffuse = gl_FrontMaterial.diffuse.rgb * max(0.0, dot(-N, gl_LightSource[0].position.xyz));\n"
- " vec4 ambientColor = gl_FrontLightModelProduct.sceneColor + gl_LightSource[0].ambient * gl_FrontMaterial.ambient;\n"
- " gl_FrontColor = ambientColor + gl_LightSource[0].diffuse * vec4(diffuse, 1.0);\n"
- " gl_BackColor = ambientColor + gl_LightSource[0].diffuse * vec4(backDiffuse, 1.0)\n;"
-// " gl_TexCoord[0] = gl_MultiTexCoord0;\n"
- " float fogCoord = abs(ecPosition.z);\n"
- " fogFactor = exp( -gl_Fog.density * gl_Fog.density * fogCoord * fogCoord);\n"
- " fogFactor = clamp(fogFactor, 0.0, 1.0);\n"
- "}\n";
-
-static char fragmentShaderSource[] =
- "uniform sampler2D baseTexture; \n"
- "varying vec2 texcoord;\n"
-// "varying vec3 N;\n"
-// "varying vec3 v;\n"
- "varying float fogFactor;\n"
- "\n"
- "void main(void) \n"
- "{ \n"
- " vec4 base = texture2D( baseTexture, texcoord);\n"
-
- " vec4 finalColor = base * gl_Color;\n"
- " gl_FragColor = mix(gl_Fog.color, finalColor, fogFactor );\n"
- "}\n";
+void addTreeToLeafGeode(Geode* geode, const SGVec3f& p)
+{
+ Vec3 pos = toOsg(p);
+ unsigned int numDrawables = geode->getNumDrawables();
+ Geometry* geom
+ = static_cast<Geometry*>(geode->getDrawable(numDrawables - 1));
+ Vec3Array* posArray = static_cast<Vec3Array*>(geom->getColorArray());
+ if (posArray->size()
+ >= static_cast<Vec3Array*>(geom->getVertexArray())->size()) {
+ Vec3Array* paramsArray
+ = static_cast<Vec3Array*>(geom->getNormalArray());
+ Vec3 params = (*paramsArray)[0];
+ geom = createTreeGeometry(params.x(), params.y(), params.z());
+ posArray = static_cast<Vec3Array*>(geom->getColorArray());
+ geode->addDrawable(geom);
+ }
+ posArray->insert(posArray->end(), 4, pos);
+ size_t numVerts = posArray->size();
+ for (int i = 0; i < 2; ++i) {
+ DrawArrays* primSet
+ = static_cast<DrawArrays*>(geom->getPrimitiveSet(i));
+ primSet->setCount(numVerts);
+ }
+}
-typedef std::map<std::string, osg::ref_ptr<StateSet> > StateSetMap;
+typedef std::map<std::string, osg::ref_ptr<Effect> > EffectMap;
-static StateSetMap treeTextureMap;
+static EffectMap treeEffectMap;
// Helper classes for creating the quad tree
namespace
{
struct MakeTreesLeaf
{
- MakeTreesLeaf(float range, Geometry* geometry, int varieties) :
- _range(range), _geometry(geometry), _varieties(varieties)
- {}
+ MakeTreesLeaf(float range, int varieties, float width, float height,
+ Effect* effect) :
+ _range(range), _varieties(varieties),
+ _width(width), _height(height), _effect(effect) {}
+
MakeTreesLeaf(const MakeTreesLeaf& rhs) :
- _range(rhs._range), _geometry(rhs._geometry), _varieties(rhs._varieties) {}
+ _range(rhs._range),
+ _varieties(rhs._varieties), _width(rhs._width), _height(rhs._height),
+ _effect(rhs._effect)
+ {}
+
LOD* operator() () const
{
LOD* result = new LOD;
- Geode* geode = new Geode;
- ShaderGeometry* sg = new ShaderGeometry(_varieties);
- sg->setGeometry(_geometry);
- geode->addDrawable(sg);
- result->addChild(geode, 0, _range);
+
+ // Create a series of LOD nodes so trees cover decreases slightly
+ // gradually with distance from _range to 2*_range
+ for (float i = 0.0; i < SG_TREE_FADE_OUT_LEVELS; i++)
+ {
+ EffectGeode* geode = createTreeGeode(_width, _height, _varieties);
+ geode->setEffect(_effect.get());
+ result->addChild(geode, 0, _range * (1.0 + i / (SG_TREE_FADE_OUT_LEVELS - 1.0)));
+ }
return result;
}
float _range;
int _varieties;
- Geometry* _geometry;
+ float _width;
+ float _height;
+ ref_ptr<Effect> _effect;
};
struct AddTreesLeafObject
{
void operator() (LOD* lod, const TreeBin::Tree& tree) const
{
- Geode* geode = static_cast<Geode*>(lod->getChild(0));
- ShaderGeometry* sg
- = static_cast<ShaderGeometry*>(geode->getDrawable(0));
- sg->addTree(tree);
+ Geode* geode = static_cast<Geode*>(lod->getChild(int(tree.position.x() * 10.0f) % lod->getNumChildren()));
+ addTreeToLeafGeode(geode, tree.position);
}
};
struct GetTreeCoord
{
- GetTreeCoord(const Matrix& transform) : _transform(transform) {}
- GetTreeCoord(const GetTreeCoord& rhs) : _transform(rhs._transform) {}
Vec3 operator() (const TreeBin::Tree& tree) const
{
- return tree.position.osg() * _transform;
+ return toOsg(tree.position);
}
- Matrix _transform;
};
typedef QuadTreeBuilder<LOD*, TreeBin::Tree, MakeTreesLeaf, AddTreesLeafObject,
GetTreeCoord> ShaderGeometryQuadtree;
}
-osg::Group* createForest(TreeBin& forest, const osg::Matrix& transform)
+struct TreeTransformer
{
- // Set up some shared structures.
- osg::Geometry* shared_geometry = createOrthQuads(forest.width,
- forest.height,
- forest.texture_varieties,
- transform);
+ TreeTransformer(Matrix& mat_) : mat(mat_) {}
+ TreeBin::Tree operator()(const TreeBin::Tree& tree) const
+ {
+ Vec3 pos = toOsg(tree.position);
+ return TreeBin::Tree(toSG(pos * mat));
+ }
+ Matrix mat;
+};
- ref_ptr<Group> group;
+// This actually returns a MatrixTransform node. If we rotate the whole
+// forest into the local Z-up coordinate system we can reuse the
+// primitive tree geometry for all the forests of the same type.
- osg::StateSet* stateset = 0;
- StateSetMap::iterator iter = treeTextureMap.find(forest.texture);
- if (iter == treeTextureMap.end()) {
- osg::Texture2D *tex = new osg::Texture2D;
- tex->setWrap( osg::Texture2D::WRAP_S, osg::Texture2D::CLAMP );
- tex->setWrap( osg::Texture2D::WRAP_T, osg::Texture2D::CLAMP );
- tex->setImage(osgDB::readImageFile(forest.texture));
-
- static ref_ptr<AlphaFunc> alphaFunc;
- static ref_ptr<Program> program;
- static ref_ptr<Uniform> baseTextureSampler;
- static ref_ptr<Material> material;
-
- stateset = new osg::StateSet;
- stateset->setTextureAttributeAndModes(0, tex, osg::StateAttribute::ON );
- stateset->setRenderBinDetails(RANDOM_OBJECTS_BIN, "DepthSortedBin");
- if (!program.valid()) {
- alphaFunc = new AlphaFunc;
- alphaFunc->setFunction(AlphaFunc::GEQUAL,0.33f);
- program = new Program;
- baseTextureSampler = new osg::Uniform("baseTexture", 0);
- Shader* vertex_shader = new Shader(Shader::VERTEX, vertexShaderSource);
- program->addShader(vertex_shader);
- program->addBindAttribLocation("textureIndex", 1);
-
- Shader* fragment_shader = new Shader(Shader::FRAGMENT,
- fragmentShaderSource);
- program->addShader(fragment_shader);
- material = new Material;
- // DonĀ“t track vertex color
- material->setColorMode(Material::OFF);
- material->setAmbient(Material::FRONT_AND_BACK,
- Vec4(.8f, .8f, .8f, 1.0f));
- material->setDiffuse(Material::FRONT_AND_BACK,
- Vec4(.2f, .2f, .2f, 1.0f));
+osg::Group* createForest(SGTreeBinList& forestList, const osg::Matrix& transform)
+{
+ Matrix transInv = Matrix::inverse(transform);
+ static Matrix ident;
+ // Set up some shared structures.
+ ref_ptr<Group> group;
+ MatrixTransform* mt = new MatrixTransform(transform);
+
+ SGTreeBinList::iterator i;
+
+ for (i = forestList.begin(); i != forestList.end(); ++i) {
+ TreeBin* forest = *i;
+
+ Effect* effect = 0;
+ EffectMap::iterator iter = treeEffectMap.find(forest->texture);
+ if (iter == treeEffectMap.end()) {
+ SGPropertyNode_ptr effectProp = new SGPropertyNode;
+ makeChild(effectProp, "inherits-from")->setStringValue("Effects/tree");
+ SGPropertyNode* params = makeChild(effectProp, "parameters");
+ // emphasize n = 0
+ params->getChild("texture", 0, true)->getChild("image", 0, true)
+ ->setStringValue(forest->texture);
+ effect = makeEffect(effectProp, true);
+ treeEffectMap.insert(EffectMap::value_type(forest->texture, effect));
+ } else {
+ effect = iter->second.get();
}
- stateset->setAttributeAndModes(alphaFunc.get());
- stateset->setAttribute(program.get());
- stateset->addUniform(baseTextureSampler.get());
- stateset->setMode(GL_VERTEX_PROGRAM_TWO_SIDE, StateAttribute::ON);
- stateset->setAttribute(material.get());
-
- treeTextureMap.insert(StateSetMap::value_type(forest.texture,
- stateset));
- } else {
- stateset = iter->second.get();
- }
- // Now, create a quadtree for the forest.
- {
- ShaderGeometryQuadtree quadtree(GetTreeCoord(Matrix::inverse(transform)),
- AddTreesLeafObject(),
- SG_TREE_QUAD_TREE_DEPTH,
- MakeTreesLeaf(forest.range,
- shared_geometry,
- forest.texture_varieties));
- quadtree.buildQuadTree(forest._trees.begin(), forest._trees.end());
+
+ // Now, create a quadtree for the forest.
+ ShaderGeometryQuadtree
+ quadtree(GetTreeCoord(), AddTreesLeafObject(),
+ SG_TREE_QUAD_TREE_DEPTH,
+ MakeTreesLeaf(forest->range, forest->texture_varieties,
+ forest->width, forest->height, effect));
+ // Transform tree positions from the "geocentric" positions we
+ // get from the scenery polys into the local Z-up coordinate
+ // system.
+ std::vector<TreeBin::Tree> rotatedTrees;
+ rotatedTrees.reserve(forest->_trees.size());
+ std::transform(forest->_trees.begin(), forest->_trees.end(),
+ std::back_inserter(rotatedTrees),
+ TreeTransformer(transInv));
+ quadtree.buildQuadTree(rotatedTrees.begin(), rotatedTrees.end());
group = quadtree.getRoot();
+
+ for (size_t i = 0; i < group->getNumChildren(); ++i)
+ mt->addChild(group->getChild(i));
}
- group->setStateSet(stateset);
- return group.release();
+
+ return mt;
}
}