GlScene.h

/*
 *
 * This file is part of Tulip (https://tulip.labri.fr)
 *
 * Authors: David Auber and the Tulip development Team
 * from LaBRI, University of Bordeaux
 *
 * Tulip is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation, either version 3
 * of the License, or (at your option) any later version.
 *
 * Tulip 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.
 *
 */
 
#ifndef Tulip_GLSCENE_H
#define Tulip_GLSCENE_H
 
#include <climits>
 
#include <tulip/tulipconf.h>
#include <tulip/BoundingBox.h>
#include <tulip/GlLODCalculator.h>
#include <tulip/GlLayer.h>
#include <tulip/Color.h>
#include <tulip/Observable.h>
 
namespace tlp {
 
class GlSimpleEntity;
class Graph;
class GlGraphComposite;
 
/**
 * @ingroup OpenGL
 * @brief Structure to store selected entities
 *
 * After a selection, objects of SelectedEntity is returned
 * To use this object the first thing to do is to call getEntity type to know the type of Entity
 * After that you can :
 *   - Get the GlSimpleEntity pointer (getSimpleEntity())
 *   - Get the id of node/edge and the graph associated (getComplexEntityId() and
 * getComplexEntityGraph())
 *
 */
struct SelectedEntity {
 
  enum SelectedEntityType {
    UNKNOW_SELECTED = 0,
    NODE_SELECTED = 1,
    EDGE_SELECTED = 2,
    SIMPLE_ENTITY_SELECTED = 3
  };
 
  SelectedEntity()
      : simpleEntity(nullptr), complexEntityId(UINT_MAX), entityType(UNKNOW_SELECTED) {}
  SelectedEntity(GlSimpleEntity *entity)
      : simpleEntity(entity), complexEntityId(UINT_MAX), entityType(SIMPLE_ENTITY_SELECTED) {}
  SelectedEntity(Graph *graph, unsigned int id, SelectedEntityType type)
      : complexEntityGraph(graph), complexEntityId(id), entityType(type) {
    assert((type == NODE_SELECTED) || (type == EDGE_SELECTED));
  }
 
  GlSimpleEntity *getSimpleEntity() const {
    assert((entityType == SIMPLE_ENTITY_SELECTED) && (simpleEntity != nullptr));
    return simpleEntity;
  }
 
  unsigned int getComplexEntityId() const {
    assert((entityType != SIMPLE_ENTITY_SELECTED) && (complexEntityId != UINT_MAX));
    return complexEntityId;
  }
 
  Graph *getComplexEntityGraph() const {
    assert((entityType != SIMPLE_ENTITY_SELECTED) && (complexEntityGraph != nullptr));
    return complexEntityGraph;
  }
 
  SelectedEntityType getEntityType() const {
    return entityType;
  }
  /**
   * @return the selected node if the entity type is correct or an invalid node else.
   */
  node getNode() const {
    assert((entityType == NODE_SELECTED) || (complexEntityId == UINT_MAX));
    return node(complexEntityId);
  }
 
  /**
   * @return the selected edge if the entity type is correct or an invalid edge else.
   */
  edge getEdge() const {
    assert((entityType == EDGE_SELECTED) || (complexEntityId == UINT_MAX));
    return edge(complexEntityId);
  }
 
protected:
  union {
    GlSimpleEntity *simpleEntity;
    Graph *complexEntityGraph;
  };
  unsigned int complexEntityId;
  SelectedEntityType entityType;
};
 
/**
 * @ingroup OpenGL
 * @brief Tulip scene class
 *
 * The GlScene class is the core of the tulip rendering system
 * This class is used to render entities and graph in OpenGL
 *
 * If you want to render entities and graph, you have to use GlLayer system. You just have to create
 * GlLayer and add GlEntity in.
 * If you create more than one GlLayer, layers are rendered one after one, so the first GlLayer
 * added is rendered in first.
 * @see GlLayer
 * @see GlSimpleEntity
 *
 *
 * After adding layers you can do a centerScene() and a draw()
 *
 * \code
 * GlLayer *mainLayer=new GlLayer("Main");
 * GlGraphComposite *graphComposite=new GlGraphComposite(graph);
 * mainLayer->addGlEntity(graphComposite,"graph");
 * GlLayer *otherLayer=new GlLayer("Other");
 * GlCircle *circle=new GlCircle();
 * otherLayer->addGlEntity(circle,"circle");
 * glScene.addLayer(mainLayer);
 * glScene.addLayer(otherLayer);
 * glScene.centerScene();
 * glScene.draw();
 * \endcode
 *
 * If you want to create a widget with a visualisation is better to use GlMainWidget class (this
 * class use a GlScene inside)
 */
class TLP_GL_SCOPE GlScene : public Observable {
 
public:
  /** \brief Constructor
   * Default scene is empty
   * @param calculator By default GlScene use a GlCPULODCalculator to compute LOD but you can change
   * this default lod calculator, to do that : put your calculator in constructor parameters
   * Available calculators are : GlCPULODCalculator and GlQuadTreeLODCalculator
   */
  GlScene(GlLODCalculator *calculator = nullptr);
 
  ~GlScene() override;
 
  /**
   * @brief Init scene's OpenGL parameters.
   * You don't have to call this function, it is call when you do a draw
   */
  void initGlParameters();
 
  /**
   * @brief Draw the scene
   * This function is the most important function of GlScene. If you want to render a scene into an
   * OpenGL widget : call this function
   */
  void draw();
 
  /**
   * Center scene
   * After this function all entities are visible on the screen
   */
  void centerScene();
 
  /**
   * Compute information for adjustSceneToSize
   * @param width request width
   * @param height request height
   * @param center the result center will be stored in (if center != nullptr)
   * @param eye the result eye will be stored in (if eye != nullptr)
   * @param sceneRadius the result sceneRadius will be stored in (if sceneRadius != nullptr)
   * @param xWhiteFactor the white part on x borders (left and right), the computed empty space size
   * will be stored in (if xWhiteFactor != nullptr)
   * @param yWhiteFactor the white part on y borders (top and bottom), the computed empty space size
   * will be stored in (if yWhiteFactor != nullptr)
   * @param sceneBoundingBox the computed sceneBoundingBox will be stored in (if sceneBoundingBox !=
   * nullptr)
   * @param zoomFactor the computed zoomFactor will be stored in (if zoomFactor != nullptr)
   */
  void computeAdjustSceneToSize(int width, int height, Coord *center, Coord *eye,
                                float *sceneRadius, float *xWhiteFactor, float *yWhiteFactor,
                                BoundingBox *sceneBoundingBox = nullptr,
                                float *zoomFactor = nullptr);
 
  /**
   * Adjust camera to have entities near borders
   * @param width requested width
   * @param height requested height
   */
  void adjustSceneToSize(int width, int height);
 
  /**
   * @brief Zoom by step to given x,y screen coordinates
   * @param step of zoom
   */
  void zoomXY(int step, const int x, const int y);
 
  /**
   * @brief Zoom by factor
   * @param factor of zoom
   */
  void zoomFactor(float factor);
 
  /**
   * @brief Zoom to given world coordinate
   * \warning factor parameter isn't be used
   */
  void zoom(float factor, const Coord &dest);
 
  /**
   * @brief Zoom by step
   * @param step of zoom
   */
  void zoom(int step) {
    zoomFactor(powf(1.1f, step));
  }
 
  /**
   * @brief Translate camera by (x,y,z)
   */
  void translateCamera(const int x, const int y, const int z);
 
  /**
   * @brief Rotate camera by (x,y,z)
   * @param x rotation over X axis in degree
   * @param y rotation over Y axis in degree
   * @param z rotation over Z axis in degree
   */
  void rotateCamera(const int x, const int y, const int z);
 
  /**
   * @brief Select entities in scene
   * @param type Entities type to select (SelectSimpleEntities,SelectNodes,SelectEdges)
   * @param x screen coordinates
   * @param y screen coordinates
   * @param h height in screen coordinates
   * @param w width in screen coordinates
   * @param layer where the selection will be performed
   * @param selectedEntities the result of the selection is stored on it
   */
  bool selectEntities(RenderingEntitiesFlag type, int x, int y, int h, int w, GlLayer *layer,
                      std::vector<SelectedEntity> &selectedEntities);
 
  /**
   * @brief Return the RGB image of GlScene
   */
  unsigned char *getImage();
 
  /**
   * @brief Set the viewport of the scene with a vector
   * The viewport must be in many case the size of the widget containing the scene
   */
  void setViewport(Vector<int, 4> &newViewport) {
    viewport = newViewport;
  }
 
  /**
   * @brief Set the viewport of the scene with 4 int
   * The viewport must be in many case the size of the widget containing the scene
   */
  void setViewport(int x, int y, int width, int height) {
    viewport[0] = x;
    viewport[1] = y;
    viewport[2] = width;
    viewport[3] = height;
  }
 
  /**
   * @brief Get the viewport of the scene
   * The viewport will be in many case the size of the widget containing the scene
   */
  const Vector<int, 4> &getViewport() const {
    return viewport;
  }
 
  /**
   * @brief Set the background color of the scene
   */
  void setBackgroundColor(const Color &color) {
    backgroundColor = color;
  }
 
  /**
   * @brief Get the background color of the scene
   */
  Color getBackgroundColor() const {
    return backgroundColor;
  }
 
  /**
   * @brief Set if scene is render in orthogonal mode
   */
  void setViewOrtho(bool viewOrtho) {
    this->viewOrtho = viewOrtho;
  }
 
  /**
   * @brief Scene is render in orthogonal mode ?
   */
  bool isViewOrtho() {
    return viewOrtho;
  }
 
  /**
   * @brief Create a layer with the given name in the scene
   * This layer is added to the layers list
   * Now the scene have the ownership of this GlLayer
   * so you don't have to delete this GlLayer
   */
  GlLayer *createLayer(const std::string &name);
 
  /**
   * @brief Create a layer with the given name in the scene just before layer with given name
   * This layer is added to the layers list
   * Return nullptr if the layer with beforeLayerWithName is not find
   * Now the scene have the ownership of this GlLayer
   * so you don't have to delete this GlLayer
   */
  GlLayer *createLayerBefore(const std::string &layerName, const std::string &beforeLayerWithName);
 
  /**
   * @brief Create a layer with the given name in the scene just after layer with given name
   * This layer is added to the layers list
   * Return nullptr if the layer with beforeLayerWithName is not find
   * Now the scene have the ownership of this GlLayer
   * so you don't have to delete this GlLayer
   */
  GlLayer *createLayerAfter(const std::string &layerName, const std::string &afterLayerWithName);
 
  /**
   * @brief Add an existing layer in the scene
   * Now the scene have the ownership of this GlLayer
   * so you don't have to delete this GlLayer
   */
  void addExistingLayer(GlLayer *layer);
 
  /**
   * @brief Add an existing layer in the scene just before layer with given name
   * Return false if the layer with beforeLayerWithName is not find
   * Now the scene have the ownership of this GlLayer
   * so you don't have to delete this GlLayer
   */
  bool addExistingLayerBefore(GlLayer *layer, const std::string &beforeLayerWithName);
 
  /**
   * @brief Add an existing layer in the scene just after layer with given name
   * Return false if the layer with beforeLayerWithName is not find
   * Now the scene have the ownership of this GlLayer
   * so you don't have to delete this GlLayer
   */
  bool addExistingLayerAfter(GlLayer *layer, const std::string &afterLayerWithName);
 
  /**
   * @brief Return the layer with name : name
   * Return nullptr if the layer doesn't exist in the scene
   */
  GlLayer *getLayer(const std::string &name);
 
  /**
   * @brief Remove the layer with name
   * This GlLayer is automatically deleted
   * If you want to keep this GlLayer you can put false to deleteLayer parameters
   * but after that you have the ownership of the GlLayer
   */
  void removeLayer(const std::string &name, bool deleteLayer = true);
 
  /**
   * @brief Remove the layer with name
   * This GlLayer is automatically deleted
   * If you want to keep this GlLayer you can put false to deleteLayer parameters
   * but after that you have the ownership of the GlLayer
   */
  void removeLayer(GlLayer *layer, bool deleteLayer = true);
 
  /**
   * @brief Return the layer list
   */
  const std::vector<std::pair<std::string, GlLayer *>> &getLayersList() {
    return layersList;
  }
 
  /**
   * @brief Clear layers list
   * Layers will not be deleted in this function
   */
  void clearLayersList() {
    for (auto &it : layersList)
      delete it.second;
 
    layersList.clear();
  }
 
  /**
   * @brief Get XML description of the scene and children and store it in out string
   */
  void getXML(std::string &out);
 
  /**
   * @brief Get XML description of cameras of the scene and store it in out string
   */
  void getXMLOnlyForCameras(std::string &out);
 
  /**
   * @brief Set scene's data and children with a XML
   */
  void setWithXML(std::string &in, Graph *graph);
 
  /**
   * @brief Return lod calculator used to render this scene
   */
  GlLODCalculator *getCalculator() {
    return lodCalculator;
  }
 
  /**
   * @brief Set a new lod calculator used to render this scene
   */
  void setCalculator(GlLODCalculator *calculator) {
    lodCalculator = calculator;
    calculator->setScene(*this);
  }
 
  /**
   * @brief Return the bounding box of the scene (in 3D coordinates)
   * \warning This bounding box is computed in rendering, so if you add an entity in a layer the
   * bounding box includes this entity if a draw is called
   */
  BoundingBox getBoundingBox();
 
  /**
   * @brief Return the current GlGraphComposite used by the scene
   */
  GlGraphComposite *getGlGraphComposite() {
    return glGraphComposite;
  }
 
  /**
   * @brief Return the layer containing the current GlGraphComposite
   */
  GlLayer *getGraphLayer() {
    return graphLayer;
  }
 
  /**
   * @brief By default the most important layer is the layer where the graph is visualized
   * This function return the camera of this layer
   */
  Camera &getGraphCamera() {
    assert(graphLayer != nullptr);
    return graphLayer->getCamera();
  }
 
  /**
   * @brief By default the most important layer is the layer where the graph is visualized
   * This function set the camera of this layer
   */
  void setGraphCamera(Camera *camera) {
    assert(graphLayer != nullptr);
    graphLayer->setCamera(camera);
  }
 
  /**
   * @brief Set if OpenGL buffer will be cleared at draw
   */
  void setClearBufferAtDraw(bool clear) {
    clearBufferAtDraw = clear;
  }
 
  /**
   * @brief If false, color buffer will not be cleared before drawing the scene.
   */
  bool getClearBufferAtDraw() const {
    return clearBufferAtDraw;
  }
 
  /**
   * @brief Set if OpenGL depth buffer will be cleared at draw
   */
  void setClearDepthBufferAtDraw(bool clear) {
    clearDepthBufferAtDraw = clear;
  }
 
  /**
   * @brief If false, depth buffer will not be cleared before drawing the scene.
   */
  bool getClearDepthBufferAtDraw() const {
    return clearDepthBufferAtDraw;
  }
 
  /**
   * @brief Set if OpenGL stencil buffer will be cleared at draw
   */
  void setClearStencilBufferAtDraw(bool clear) {
    clearStencilBufferAtDraw = clear;
  }
 
  /**
   * @brief If false, color buffer will not be cleared before drawing the scene.
   */
  bool getClearStencilBufferAtDraw() const {
    return clearStencilBufferAtDraw;
  }
 
private:
  std::vector<std::pair<std::string, GlLayer *>> layersList;
  GlLODCalculator *lodCalculator;
  Vector<int, 4> viewport;
  Color backgroundColor;
  bool viewOrtho;
 
  GlGraphComposite *glGraphComposite;
  GlLayer *graphLayer;
 
  bool clearBufferAtDraw;
 
  bool inDraw;
 
  bool clearDepthBufferAtDraw;
 
  bool clearStencilBufferAtDraw;
 
public:
  ///@cond DOXYGEN_HIDDEN
 
  /**
   * @brief You don't have to call this function
   * This function is automatically called when a GlGraphComposite is added in a layer in the scene
   * You don't have to call this function
   */
  void glGraphCompositeAdded(GlLayer *layer, GlGraphComposite *composite);
 
  /**
   * @brief You don't have to call this function
   * This function is automatically called when a GlGraphComposite is added in a layer in the scene
   * You don't have to call this function
   */
  void glGraphCompositeRemoved(GlLayer *layer, GlGraphComposite *composite);
 
  /**
   * @brief You don't have to call this function
   * This function is called by GlLayer and GlComposite to send layer modification event
   */
  void notifyModifyLayer(const std::string &name, GlLayer *layer);
 
  /**
   * @brief You don't have to call these functions
   * They are called by GlComposite to send entity modification event
   */
  void notifyModifyEntity(GlSimpleEntity *entity);
  void notifyDeletedEntity(GlSimpleEntity *entity);
 
  ///@endcond
};
} // namespace tlp
 
#endif // Tulip_GLSCENE_H