]> git.tdb.fi Git - libs/gl.git/commitdiff
Add class Technique to share passes between Objects
authorMikko Rasa <tdb@tdb.fi>
Sat, 4 Oct 2008 20:26:55 +0000 (20:26 +0000)
committerMikko Rasa <tdb@tdb.fi>
Sat, 4 Oct 2008 20:26:55 +0000 (20:26 +0000)
Refactor Object to make use of Technique and also work without one
Make ObjectInstance take a Tag instead of ObjectPass in (prepare|finish)_render

source/object.cpp
source/object.h
source/objectinstance.h
source/technique.cpp [new file with mode: 0644]
source/technique.h [new file with mode: 0644]

index db2866115a05561500843a7c7b0c7540b3be328c..b53a3f0802767e9e6e80b7a6e1d0434aa4d0c474 100644 (file)
@@ -14,6 +14,7 @@ Distributed under the LGPL
 #include "objectpass.h"
 #include "program.h"
 #include "programdata.h"
+#include "technique.h"
 #include "texture.h"
 #include "texunit.h"
 
@@ -24,66 +25,74 @@ namespace GL {
 
 Object::Object():
        meshes(1, static_cast<Mesh *>(0)),
+       technique(0),
        main_texture(0),
        material(0)
-{
-       normal_pass=&passes[0];
-}
+{ }
 
 Object::~Object()
 {
-       for(map<unsigned, ObjectPass>::iterator i=passes.begin(); i!=passes.end(); ++i)
-               delete i->second.shdata;
 }
 
 bool Object::has_pass(const Tag &tag) const
 {
-       return passes.count(tag.id);
+       if(technique)
+               return technique->has_pass(tag);
+       else
+               return tag.id==0;
 }
 
-const ObjectPass &Object::get_pass(const Tag &tag) const
+void Object::render(const Tag &tag) const
 {
-       map<unsigned, ObjectPass>::const_iterator i=passes.find(tag.id);
-       if(i==passes.end())
-               throw KeyError("Unknown pass");
-       return i->second;
+       const ObjectPass *pass=get_pass(tag);
+       setup_render(pass);
+       meshes[0]->draw();
+       finish_render(pass);
 }
 
-void Object::render(const Tag &tag) const
+void Object::render(const ObjectInstance &inst, const Tag &tag) const
 {
-       render(get_pass(tag), 0);
+       const ObjectPass *pass=get_pass(tag);
+       setup_render(pass);
+       render_instance(inst, tag);
+       meshes[0]->draw();
+       finish_render(pass);
 }
 
-void Object::render(const ObjectInstance &inst, const Tag &tag) const
+const ObjectPass *Object::get_pass(const Tag &tag) const
 {
-       render(get_pass(tag), &inst);
+       if(technique)
+               return &technique->get_pass(tag);
+       else if(tag.id==0)
+               return 0;
+       throw KeyError("Unknown pass");
 }
 
-void Object::setup_render(const ObjectPass &pass) const
+void Object::setup_render(const ObjectPass *pass) const
 {
        if(!meshes[0])
                throw InvalidState("Trying to render Object without mesh");
 
-       if(pass.shprog)
+       if(pass && pass->shprog)
        {
-               pass.shprog->bind();
-               pass.shdata->apply();
+               pass->shprog->bind();
+               pass->shdata->apply();
                for(unsigned i=0; i<textures.size(); ++i)
                {
                        TexUnit::activate(i);
                        textures[i]->bind();
                }
        }
-       else if(main_texture && pass.use_textures)
+       else if(main_texture && (!pass || pass->use_textures))
                main_texture->bind();
 
        if(material)
                material->bind();
 }
 
-void Object::finish_render(const ObjectPass &pass) const
+void Object::finish_render(const ObjectPass *pass) const
 {
-       if(pass.shprog)
+       if(pass && pass->shprog)
        {
                Program::unbind();
                for(unsigned i=textures.size(); i--;)
@@ -99,24 +108,12 @@ void Object::finish_render(const ObjectPass &pass) const
                Material::unbind();
 }
 
-void Object::render(const ObjectPass &pass, const ObjectInstance *inst) const
-{
-       setup_render(pass);
-
-       if(inst)
-               render_instance(pass, *inst);
-       else
-               meshes[0]->draw();
-
-       finish_render(pass);
-}
-
-void Object::render_instance(const ObjectPass &pass, const ObjectInstance &inst) const
+void Object::render_instance(const ObjectInstance &inst, const Tag &tag) const
 {
-       inst.setup_render(pass);
+       inst.setup_render(tag);
        unsigned lod=min(inst.get_level_of_detail(), meshes.size()-1);
        meshes[lod]->draw();
-       inst.finish_render(pass);
+       inst.finish_render(tag);
 }
 
 
@@ -128,20 +125,22 @@ Object::Loader::Loader(Object &o, Collection &c):
        add("material", &Object::material);
        add("material_inline", &Loader::material_inline);
        add("mesh",     &Loader::mesh);
-       add("pass",     &Loader::pass);
-       add("shader",   &Loader::shader);
        add("shader_texture", &Loader::shader_texture);
+       add("technique", &Loader::technique);
        add("texture",  &Loader::texture);
 }
 
 void Object::Loader::finish()
 {
-       for(map<unsigned, ObjectPass>::iterator i=obj.passes.begin(); i!=obj.passes.end(); ++i)
-               if(i->second.shdata)
+       for(unsigned i=0; i<obj.textures.size(); ++i)
+       {
+               if(!obj.textures[i])
                {
-                       for(unsigned j=0; j<textures.size(); ++j)
-                               i->second.shdata->uniform(i->second.shprog->get_uniform_location(textures[j]), static_cast<int>(j));
+                       obj.textures[i]=obj.technique->get_texture(i);
+                       if(!obj.textures[i])
+                               throw Exception("Object does not specify all textures required by Technique");
                }
+       }
 }
 
 void Object::Loader::lod_mesh(unsigned l, const string &n)
@@ -154,7 +153,7 @@ void Object::Loader::material_inline()
 {
        RefPtr<Material> mat=new Material;
        load_sub(*mat);
-       coll.add(format("%p%p", &obj, mat.get()), mat.get());
+       coll.add(format("_%p", mat.get()), mat.get());
        obj.material=mat.release();
 }
 
@@ -163,44 +162,23 @@ void Object::Loader::mesh(const string &n)
        obj.meshes[0]=coll.get<Mesh>(n);
 }
 
-void Object::Loader::pass(const string &n)
+void Object::Loader::shader_texture(const string &n)
 {
-       unsigned id=Tag(n).id;
-       if(obj.passes.count(id))
-               throw KeyError("Duplicate pass name");
-       ObjectPass p;
-       load_sub(p, coll);
-       obj.passes[id]=p;
-}
+       if(!obj.technique)
+               throw InvalidState("Can't specify shader textures without a Technique");
 
-void Object::Loader::shader(const string &n)
-{
-       Program *shprog=coll.get<Program>(n);
-       if(shprog)  // Allow for unsupported shaders
-       {
-               RefPtr<ProgramData> shdata=new ProgramData;
-               load_sub(*shdata, *shprog);
+       unsigned eqsign=n.find('=');
+       if(eqsign==string::npos)
+               throw InvalidParameterValue("Must specify texture slot name");
 
-               obj.normal_pass->shprog=shprog;
-               if(obj.normal_pass->shdata)
-                       delete obj.normal_pass->shdata;
-               obj.normal_pass->shdata=shdata.release();
-       }
+       obj.textures[obj.technique->get_texture_index(n.substr(0, eqsign))]=coll.get<Texture>(n.substr(eqsign+1));
 }
 
-void Object::Loader::shader_texture(const string &n)
+void Object::Loader::technique(const string &n)
 {
-       unsigned eqsign=n.find('=');
-       if(eqsign!=string::npos)
-       {
-               obj.textures.push_back(coll.get<Texture>(n.substr(eqsign+1)));
-               textures.push_back(n.substr(0, eqsign));
-       }
-       else
-       {
-               obj.textures.push_back(coll.get<Texture>(n));
-               textures.push_back(n);
-       }
+       obj.technique=coll.get<Technique>(n);
+       obj.textures.resize(obj.technique->get_n_textures());
+       obj.material=obj.technique->get_material();
 }
 
 void Object::Loader::texture(const string &n)
@@ -208,9 +186,10 @@ void Object::Loader::texture(const string &n)
        if(obj.main_texture)
                throw Exception("Only one main texture may be specified");
 
-       obj.main_texture=coll.get<Texture>(n);
-       obj.textures.push_back(obj.main_texture);
-       textures.push_back("texture");
+       Texture *tex=coll.get<Texture>(n);
+       if(obj.technique)
+               obj.textures[obj.technique->get_texture_index("texture")]=tex;
+       obj.main_texture=tex;
 }
 
 } // namespace GL
index 42541eaf28004807d1e088f32f1281c1788b7800..9c1ea7f7fbbf9533afab934b8d20d4df24263230 100644 (file)
@@ -19,26 +19,26 @@ namespace GL {
 class Material;
 class Mesh;
 class ObjectInstance;
-class Program;
-class ProgramData;
+class Technique;
 class Texture;
 
 /**
-Stores data for a complete 3D object.  This includes a mesh, a shader and data
-for it and a number of textures.  Only the mesh is mandatory, other components
-are optional.
+Stores data for a complete 3D object.  An Object must always have a Mesh, and
+may also have a Technique to determine its appearance.  Textures and material
+specified by the Technique may be overridden.  Simple textured objects are also
+possible without a Technique.
 
-See also class ObjectInstance.
+It is possible to use a single Object for rendering multiple identical or
+similar objects.  See class ObjectInstance.
 */
 class Object: public Renderable
 {
 private:
        std::vector<const Mesh *> meshes;
+       const Technique *technique;
        std::vector<const Texture *> textures;
        const Texture *main_texture;
-       std::map<unsigned, ObjectPass> passes;
        const Material *material;
-       ObjectPass *normal_pass;
 
 public:
        class Loader: public DataFile::Loader
@@ -49,8 +49,6 @@ public:
        protected:
                Object &obj;
                Collection &coll;
-       private:
-               std::vector<std::string> textures;
        
        public:
                Loader(Object &, Collection &);
@@ -62,17 +60,17 @@ public:
                void lod_mesh(unsigned, const std::string &);
                void material_inline();
                void mesh(const std::string &);
-               void pass(const std::string &);
-               void shader(const std::string &);
                void shader_texture(const std::string &);
+               void technique(const std::string &);
                void texture(const std::string &);
        };
 
        Object();
        ~Object();
 
+       const Technique *get_technique() const { return technique; }
+
        virtual bool has_pass(const Tag &) const;
-       const ObjectPass &get_pass(const Tag &) const;
 
        /**
        Renders the object.  A tag can be provided to render a non-default pass.
@@ -94,22 +92,18 @@ public:
        */
        template<typename Iter>
        void render(Iter begin, Iter end, const Tag &tag=Tag()) const
-       { render(get_pass(tag), begin, end); }
-private:
-       void setup_render(const ObjectPass &) const;
-       void finish_render(const ObjectPass &) const;
-       void render(const ObjectPass &, const ObjectInstance *) const;
-
-       template<typename Iter>
-       void render(const ObjectPass &pass, Iter begin, Iter end) const
        {
+               const ObjectPass *pass=get_pass(tag);
                setup_render(pass);
                for(Iter i=begin; i!=end; ++i)
-                       render_instance(pass, **i);
+                       render_instance(**i, tag);
                finish_render(pass);
        }
-
-       void render_instance(const ObjectPass &, const ObjectInstance &) const;
+private:
+       const ObjectPass *get_pass(const Tag &) const;
+       void setup_render(const ObjectPass *) const;
+       void finish_render(const ObjectPass *) const;
+       void render_instance(const ObjectInstance &, const Tag &) const;
 };
 
 } // namespace GL
index 00e98791006a17eafd098cda51a2b12d5cf4809d..dbb8c627163562a4cc8211cf41ff8e2086ab2895 100644 (file)
@@ -17,8 +17,6 @@ namespace GL {
 class Object;
 class ProgramData;
 
-class ObjectPass;
-
 /**
 Represents a single instance of an Object.  An application can derive another
 class from this and overload the hook functions to specify location and other
@@ -44,12 +42,12 @@ public:
        /**
        Hook function, called from Object just before rendering the mesh.
        */
-       virtual void setup_render(const ObjectPass &) const { }
+       virtual void setup_render(const Tag &) const { }
 
        /**
        Hook function, called from Object right after rendering the mesh.
        */
-       virtual void finish_render(const ObjectPass &) const { }
+       virtual void finish_render(const Tag &) const { }
 
        virtual unsigned get_level_of_detail() const { return 0; }
 };
diff --git a/source/technique.cpp b/source/technique.cpp
new file mode 100644 (file)
index 0000000..4d2377a
--- /dev/null
@@ -0,0 +1,152 @@
+/* $Id$
+
+This file is part of libmspgl
+Copyright © 2007  Mikko Rasa, Mikkosoft Productions
+Distributed under the LGPL
+*/
+
+#include <msp/strings/formatter.h>
+#include "material.h"
+#include "program.h"
+#include "programdata.h"
+#include "tag.h"
+#include "technique.h"
+#include "texture.h"
+
+using namespace std;
+
+namespace Msp {
+namespace GL {
+
+Technique::Technique():
+       main_texture(0),
+       normal_pass(&passes[0]),
+       material(0)
+{ }
+
+Technique::~Technique()
+{
+       for(map<unsigned, ObjectPass>::iterator i=passes.begin(); i!=passes.end(); ++i)
+               delete i->second.shdata;
+}
+
+bool Technique::has_pass(const GL::Tag &tag) const
+{
+       return passes.count(tag.id);
+}
+
+const ObjectPass &Technique::get_pass(const GL::Tag &tag) const
+{
+       map<unsigned, ObjectPass>::const_iterator i=passes.find(tag.id);
+       if(i==passes.end())
+               throw KeyError("Unknown pass");
+       return i->second;
+}
+
+unsigned Technique::get_texture_index(const std::string &n) const
+{
+       for(unsigned i=0; i<tex_names.size(); ++i)
+               if(tex_names[i]==n)
+                       return i;
+
+       throw KeyError("Unknown texture slot", n);
+}
+
+const Texture *Technique::get_texture(unsigned i) const
+{
+       if(i>=textures.size())
+               throw KeyError("Texture index out of range");
+
+       return textures[i];
+}
+
+
+Technique::Loader::Loader(Technique &t, Collection &c):
+       tech(t),
+       coll(c)
+{
+       add("material",        &Technique::material);
+       add("material_inline", &Loader::material_inline);
+       add("pass",            &Loader::pass);
+       add("shader",          &Loader::shader);
+       add("shader_texture",  &Loader::shader_texture);
+       add("texture",         &Loader::texture);
+       add("texture_slot",    &Loader::texture_slot);
+}
+
+void Technique::Loader::finish()
+{
+       for(map<unsigned, ObjectPass>::iterator i=tech.passes.begin(); i!=tech.passes.end(); ++i)
+               if(i->second.shdata)
+               {
+                       for(unsigned j=0; j<tech.textures.size(); ++j)
+                               i->second.shdata->uniform(i->second.shprog->get_uniform_location(tech.tex_names[j]), static_cast<int>(j));
+               }
+}
+
+void Technique::Loader::material_inline()
+{
+       RefPtr<Material> mat=new Material;
+       load_sub(*mat);
+       coll.add(format("_%p", mat.get()), mat.get());
+       tech.material=mat.release();
+}
+
+void Technique::Loader::pass(const string &n)
+{
+       unsigned id=Tag(n).id;
+       if(tech.passes.count(id))
+               throw KeyError("Duplicate pass name", n);
+       ObjectPass p;
+       load_sub(p, coll);
+       tech.passes[id]=p;
+}
+
+void Technique::Loader::shader(const string &n)
+{
+       Program *shprog=coll.get<Program>(n);
+       if(shprog)  // Allow for unsupported shaders
+       {
+               RefPtr<ProgramData> shdata=new ProgramData;
+               load_sub(*shdata, *shprog);
+
+               tech.normal_pass->shprog=shprog;
+               if(tech.normal_pass->shdata)
+                       delete tech.normal_pass->shdata;
+               tech.normal_pass->shdata=shdata.release();
+       }
+}
+
+void Technique::Loader::shader_texture(const string &n)
+{
+       unsigned eqsign=n.find('=');
+       if(eqsign!=string::npos)
+       {
+               tech.textures.push_back(coll.get<Texture>(n.substr(eqsign+1)));
+               tech.tex_names.push_back(n.substr(0, eqsign));
+       }
+       else
+       {
+               tech.textures.push_back(coll.get<Texture>(n));
+               tech.tex_names.push_back(n);
+       }
+}
+
+void Technique::Loader::texture(const string &n)
+{
+       if(tech.main_texture)
+               throw Exception("Only one main texture may be specified");
+
+       tech.main_texture=coll.get<Texture>(n);
+       tech.textures.push_back(tech.main_texture);
+       tech.tex_names.push_back("texture");
+}
+
+void Technique::Loader::texture_slot(const string &n)
+{
+       tech.tex_names.push_back(n);
+       tech.textures.push_back(0);
+}
+
+} // namespace GL
+} // namespace Msp
diff --git a/source/technique.h b/source/technique.h
new file mode 100644 (file)
index 0000000..410e7fb
--- /dev/null
@@ -0,0 +1,75 @@
+/* $Id$
+
+This file is part of libmspgl
+Copyright © 2007  Mikko Rasa, Mikkosoft Productions
+Distributed under the LGPL
+*/
+
+#ifndef TECHNIQUE_H_
+#define TECHNIQUE_H_
+
+#include "objectpass.h"
+
+namespace Msp {
+namespace GL {
+
+class Material;
+class Tag;
+class Texture;
+
+/**
+Stores a complete multipass rendering technique for an Object.  This includes
+shaders, textures and a material.  A Technique can also specify empty texture
+slots which Objects must override.
+*/
+class Technique
+{
+public:
+       class Loader: public Msp::DataFile::Loader
+       {
+       public:
+               typedef DataFile::Collection Collection;
+
+       protected:
+               Technique &tech;
+               Collection &coll;
+       
+       public:
+               Loader(Technique &, Collection &);
+
+               Technique &get_object() const { return tech; }
+               Collection &get_collection() const { return coll; }
+       private:
+               virtual void finish();
+               void material_inline();
+               void pass(const std::string &);
+               void shader(const std::string &);
+               void shader_texture(const std::string &);
+               void texture(const std::string &);
+               void texture_slot(const std::string &);
+       };
+
+private:
+       std::vector<std::string> tex_names;
+       std::vector<const Texture *> textures;
+       const Texture *main_texture;
+       std::map<unsigned, ObjectPass> passes;
+       ObjectPass *normal_pass;
+       const Material *material;
+
+public:
+       Technique();
+       ~Technique();
+
+       bool has_pass(const GL::Tag &) const;
+       const ObjectPass &get_pass(const GL::Tag &) const;
+       unsigned get_n_textures() const { return tex_names.size(); }
+       unsigned get_texture_index(const std::string &) const;
+       const Texture *get_texture(unsigned) const;
+       const Material *get_material() const { return material; }
+};
+
+} // namespace GL
+} // namespace Msp
+
+#endif