DI-Guy Graphics API, diguyOsgExtGraphicsShape

diguyOsgExtGraphicsShape.cpp

DI-Guy API Version 12.5.1

This file was automatically generated from diguyOsgExtGraphicsShape.cpp. Do not edit this file directly; the changes will be lost.

Shapes are the high-level containers of visible geometry. They are attached to links, and contain zero or more mesh objects.

The class diguyOsgExtGraphicsShape is an example of a diguyGraphicsShape subclass for a retained renderer using an external loader. The example subclass shows how to use the accessors of the diguyGraphicsShape class and which virtual functions should be overridden for an immediate mode renderer such as Open Scene Graph.

#include "diguyOsgExtGraphicsShape.h" #include "diguyOsgExtGraphicsLink.h" #include <libbdilog.h> #include <diguyScenario.h> #include <diguyCharacter.h> /* * Top-level static variable that determines whether LOD calculations are * based strictly on distance of object from camera, or on size of object, * in pixels, in frame. */ bool diguyOsgExtGraphicsShape::s_use_pixel_lods = false;

Initialize data members of the class to a known state.

Base class data will not be fully initialized until the Build Stage is done, so base class accessors should not be called here.

diguyOsgExtGraphicsShape::diguyOsgExtGraphicsShape(void* internal_data)     :     diguyGraphicsShape(internal_data),     m_switch_node(NULL),     m_lod_node(NULL),     m_manual_lod_switch_node(NULL) {     /*      * Nothing else to do after calling base class constructor and      * initializing data members.      */ }

Build Stage

Description:

Override of diguyGraphicsShape::build().

The build() function should look up the shape's parts from previously loaded geometry files, and create the necessary objects that will apply offset data of this shape from its parent link during the Draw Stage.

This implementation creates the nodes necessary to switch the shape geometry on and off, apply lod calculations, and look up and attach nodes found in a DI-Guy geometry file.

void diguyOsgExtGraphicsShape::build() {     int lod;     diguyGraphicsLink* diguy_link = get_link();     diguyOsgExtGraphicsLink* osg_link = (diguyOsgExtGraphicsLink *) diguy_link;     osg::MatrixTransform* link_dof_node = osg_link->get_dof_node();     if (!link_dof_node)         return;     /*      * By default we'll attach meshes to the link's dof node. If this      * shape is switched, however (e.g. for switchable hands), we'll create      * a swtich node and attach them to the switch.      */     osg::Group* lod_attach_node = link_dof_node;     /*      * See if we should create a switch.      */     if (get_switch_var_name() != NULL)     {         m_switch_node = new osg::Switch();         m_switch_node->setNewChildDefaultValue(true);         link_dof_node->addChild(m_switch_node);         lod_attach_node = m_switch_node;     }     /*      * Determine whether automatic graphics LOD switching is enabled.      * This will determine which kind of node we create for LOD switching.      */     diguyCharacter* character = get_character();     diguyScenario* scenario = character ? character->get_scenario() : NULL;     int automatic_graphics_lod_switching = scenario ? scenario->get_automatic_graphics_lod_switching() : 1;     /*      * If automatic switching is enabled, create an osg::LOD() node.      */     if (automatic_graphics_lod_switching)     {         /*          * Determine the lod_ranges.          */         float* lod_ranges = get_lod_ranges();         /*          * Create an lod node.          */         m_lod_node = new osg::LOD();         m_lod_node->setCenter(osg::Vec3f(0.0f, 0.0f, 0.0f));         if (s_use_pixel_lods)             m_lod_node->setRangeMode(osg::LOD::PIXEL_SIZE_ON_SCREEN);         else             m_lod_node->setRangeMode(osg::LOD::DISTANCE_FROM_EYE_POINT);         lod_attach_node->addChild(m_lod_node);         /*          * Attach shape parts.          */         for (lod=1; lod<=get_num_lods(); lod++)         {             void* diguy_part = get_diguy_graphics_file_part(lod);             if (diguy_part)             {                 osg::Node* osg_part = (osg::Node*) diguy_part;                 if (s_use_pixel_lods)                 {                     /*                      * Because DI-Guy LOD ranges must increase at each index,                      * but unlike with distances the earlier numbers represent                      * low LODs, we have to reverse the order of lod ranges.                      *                      * LOD 1: lod_ranges[6] to lod_ranges[7]                      * LOD 2: lod_ranges[5] to lod_ranges[6]                      * etc.                      */                     m_lod_node->addChild(osg_part, lod_ranges[7 - lod], lod_ranges[8 - lod]);                 }                 else                 {                     /*                      * LOD 1: lod_ranges[0] to lod_ranges[1]                      * LOD 2: lod_ranges[1] to lod_ranges[2]                      * etc.                      */                     m_lod_node->addChild(osg_part, lod_ranges[lod-1], lod_ranges[lod]);                 }             }         }     }     /*      * Else automatic LOD switching is not enabled. Create a switch node      * for manual LOD switching.      */     else     {         m_manual_lod_switch_node = new osg::Switch();         m_manual_lod_switch_node->setNewChildDefaultValue(false);         lod_attach_node->addChild(m_manual_lod_switch_node);         /*          * Create a geode for each lod.          * Attach mesh drawables to geodes.          */         for (lod=1; lod<=get_num_lods(); lod++)         {             void* diguy_part = get_diguy_graphics_file_part(lod);             if (diguy_part)             {                 osg::Node* osg_part = (osg::Node*) diguy_part;                 m_manual_lod_switch_node->addChild(osg_part);                 m_manual_lod_switch_node->setSingleChildOn(get_graphics_lod() - 1);             }         }     } /// /* /// * Create a switch node. /// */ /// m_switch_node = new osg::Switch(); /// m_switch_node->setNewChildDefaultValue(true); /// link_dof_node->addChild(m_switch_node); /// /// /* /// * Determine the lod_ranges. /// */ /// float* lod_ranges = get_lod_ranges(); /// /// /* /// * Create an lod node. /// */ /// m_lod_node = new osg::LOD(); /// m_lod_node->setCenter(osg::Vec3f(0.0f, 0.0f, 0.0f)); /// /// m_switch_node->addChild(m_lod_node); /// /// /* /// * Attach shape parts. /// */ /// for (lod=1; lod<=get_num_lods(); lod++) /// { /// void* diguy_part = get_diguy_graphics_file_part(lod); /// if (diguy_part) /// { /// osg::Node* osg_part = (osg::Node*) diguy_part; /// m_lod_node->addChild(osg_part, lod_ranges[lod-1], lod_ranges[lod]); /// } /// } }

Unbuild Stage

Description:

Override of diguyGraphicsShape::unbuild().

The unbuild() function should destroy the objects created in the build() function.

This implementation detaches and dereferences the nodes created and attached in the build() function.

void diguyOsgExtGraphicsShape::unbuild() {     diguyGraphicsLink* diguy_link = get_link();     diguyOsgExtGraphicsLink* osg_link = (diguyOsgExtGraphicsLink *) diguy_link;     osg::MatrixTransform* link_dof_node = osg_link->get_dof_node();     if (!link_dof_node)         return;     osg::Group* lod_detach_node = link_dof_node;     /*      * Remove all of the group nodes we created and added in the build()      * call; this should reduce the ref count of the added nodes by 1, to      * 1. Then set the pointers to NULL; this should reduce the ref count      * to 0, resulting in the group nodes being deleted.      *      * Setting the m_switch_node ref_ptr to NULL dereferences the Switch      * object it points to, possibly deleting it. Ditto for m_lod_node and      * m_manual_lod_switch_node.      */     if (m_switch_node != NULL)         lod_detach_node = m_switch_node;     if (m_lod_node != NULL)     {         lod_detach_node->removeChild(m_lod_node);         m_lod_node = NULL;     }     else if (m_manual_lod_switch_node != NULL)     {         lod_detach_node->removeChild(m_manual_lod_switch_node);         m_manual_lod_switch_node = NULL;     }     if (m_switch_node != NULL)     {         link_dof_node->removeChild(m_switch_node);         m_switch_node = NULL;     } /// diguyGraphicsLink* diguy_link = get_link(); /// diguyOsgExtGraphicsLink* osg_link = (diguyOsgExtGraphicsLink *) diguy_link; /// /// osg::MatrixTransform* link_dof_node = osg_link->get_dof_node(); /// /// if (!link_dof_node) /// return; /// /// /* /// * Detach shape parts. /// */ /// int lod; /// for (lod=1; lod<=get_num_lods(); lod++) /// { /// void* diguy_part = get_diguy_graphics_file_part(lod); /// if (diguy_part) /// { /// osg::Node* osg_part = (osg::Node*) diguy_part; /// m_lod_node->removeChild(osg_part); /// } /// } /// /// /* /// * Dereference lod node. /// */ /// m_switch_node->removeChild(m_lod_node); /// m_lod_node = NULL; /// /// /* /// * Dereference switch. /// */ /// link_dof_node->removeChild(m_switch_node); /// m_switch_node = NULL; }

Update Stage

Description:

Override of diguyGraphicsShape::show().

The show() function should take the necessary steps to make the shape's visible geometry visible.

This implementation turns all children of the shape's switch node on.

void diguyOsgExtGraphicsShape::show() {     if (m_switch_node)         m_switch_node->setAllChildrenOn(); }

Update Stage

Description:

Override of diguyGraphicsShape::hide().

The hide() function should take the necessary steps to make the shape's visible geometry hidden.

This implementation turns all children of the shape's switch node off.

void diguyOsgExtGraphicsShape::hide() {     if (m_switch_node)         m_switch_node->setAllChildrenOff(); }

Override of diguyGraphicsShape::set_graphics_lod_ranges(), called as needed.

The set_graphics_lod_ranges() function should update the ranges of lod objects created in the build() function with the passed ranges.

In this implementation the ranges of the osg::LOD created in build() are updated. If automatic LOD switching is enabled, the LOD node will not exist and this function will have no effect.

void diguyOsgExtGraphicsShape::set_graphics_lod_ranges(float* lod_ranges) {     if (m_lod_node != NULL)     {         int lod;         for (lod=1; lod<=get_num_lods(); lod++)         {             m_lod_node->setRange(lod-1, lod_ranges[lod-1], lod_ranges[lod]);         }     } }

Override of diguyGraphicsShape::set_graphics_lod(), called as needed.

The set_graphics_lod() function should select and show the object representing the passed LOD.

This implementation manually sets the osg::Switch created in build() to show the correct geode. If automatic LOD switching is enabled, the switch node will not exist and this function will have no effect.

void diguyOsgExtGraphicsShape::set_graphics_lod(int lod) {     if (m_manual_lod_switch_node != NULL)     {         m_manual_lod_switch_node->setSingleChildOn(lod-1);     } }

Create and return an object of a subclass of diguyGraphicsShape. This function will be called whenever DI-Guy requires a shape object.

diguyGraphicsShape* diguyOsgExtGraphicsShape_create_func(void* internal_data) {     return new diguyOsgExtGraphicsShape(internal_data); }