source: trunk/src/gfx/skeletal_mesh.cc @ 319

// Copyright (C) 2011-2014 ChaosForge Ltd
// This file is part of NV Libraries.
// For conditions of distribution and use, see copyright notice in nv.hh

#include "nv/gfx/skeletal_mesh.hh"

#include <glm/gtc/matrix_access.hpp>
#include <glm/gtx/matrix_interpolation.hpp>
#include "nv/interface/context.hh"
#include "nv/interface/device.hh"


nv::skeletal_mesh_cpu::skeletal_mesh_cpu( context* a_context, const mesh_data* a_mesh_data, const mesh_nodes_data* bones )
        : skeletal_mesh( a_context )
        , m_data( a_mesh_data )
{
        const mesh_raw_channel* pnt_chan = a_mesh_data->get_channel<md5_vtx_pnt>();
        m_pntdata.assign( (const md5_vtx_pnt*)pnt_chan->data, pnt_chan->count );
        m_bone_offset.resize( bones->get_count() );
        m_transform.resize( bones->get_count() );

        for ( uint32 i = 0; i < bones->get_count(); ++i )
        {
                m_bone_offset[i] = transform( bones->get_node(i)->transform );
        }
        m_vtx_data  = a_mesh_data->get_channel_data<md5_vtx_pntiw>();
        m_indices   = a_mesh_data->get_count();
        m_va        = a_context->create_vertex_array( a_mesh_data, 
STREAM_DRAW );
        m_pbuffer   = a_context->find_buffer( m_va, slot::POSITION );
}

void nv::skeletal_mesh_cpu::update_animation( animation_entry* a_anim, uint32 a_anim_time )
{
        if ( a_anim )
        {
                skeletal_animation_entry_cpu * anim = (skeletal_animation_entry_cpu*)a_anim;
                anim->update_skeleton( m_transform.data(), (float)a_anim_time );
                {
                        size_t skeleton_size = m_bone_offset.size();
                        size_t vertex_count  = m_pntdata.size();
                        m_pos_offset.resize( skeleton_size );
                        for ( unsigned int i = 0; i < skeleton_size; ++i )
                        {
                                m_pos_offset[i] = m_transform[i] * m_bone_offset[i];
                        }

                        std::fill( m_pntdata.raw_data(), m_pntdata.raw_data() + m_pntdata.raw_size(), 0 );
                        for ( unsigned int i = 0; i < vertex_count; ++i )
                        {
                                const md5_vtx_pntiw& vert = m_vtx_data[i];

                                for ( size_t j = 0; j < 4; ++j )
                                {
                                        int   index  = vert.boneindex[j];
                                        float weight = vert.boneweight[j];
                                        const quat& orient      = m_transform[index].get_orientation();
                                        const transform& offset = m_pos_offset[index];
                                        m_pntdata[i].position += offset.transformed( vert.position )        * weight;
                                        m_pntdata[i].normal   += ( orient * vert.normal  ) * weight;
                                        m_pntdata[i].tangent  += ( orient * vert.tangent ) * weight;
                                }
                        }
                }

                m_context->update( m_pbuffer, m_pntdata.data(), 0, m_pntdata.raw_size() );
        }
}


void nv::skeletal_animation_entry_cpu::update_skeleton( transform* skeleton, float time ) const
{
        float frame_duration = 1000.f / (float)m_node_data->get_frame_rate();
        float anim_duration = frame_duration * m_node_data->get_duration();
        float new_time = fmodf( time, anim_duration ) * 0.001f;

        float frame_num = new_time * m_node_data->get_frame_rate();
        for ( size_t i = 0; i < m_node_data->get_count(); ++i )
        {
                skeleton[i] = m_node_data->get_node(i)->data->get_transform( frame_num );
        }
}

void nv::skeletal_animation_entry_gpu::initialize()
{
        m_prepared  = false;
        m_children  = nullptr;
        m_offsets   = nullptr;
        uint32 node_count = m_node_data->get_count();
        m_bone_ids  = new sint16[ node_count ];

        if ( !m_node_data->is_flat() )
        {
                m_children = new std::vector< uint32 >[ node_count ];
                for ( uint32 n = 0; n < node_count; ++n )
                {
                        const mesh_node_data* node = m_node_data->get_node(n);
                        if ( node->parent_id != -1 )
                        {
                                m_children[ node->parent_id ].push_back( n );
                        }
                }
        }
}

void nv::skeletal_animation_entry_gpu::update_skeleton( mat4* data, uint32 time ) const
{
        float tick_time = ( time * 0.001f ) * m_frame_rate;
        float anim_time = m_start;
        if ( m_duration > 0.0f ) anim_time += fmodf( tick_time, m_duration );

        if ( !m_node_data->is_flat() )
        {
                animate_rec( data, anim_time, 0, mat4() );
                return;
        }

        for ( uint32 n = 0; n < m_node_data->get_count(); ++n )
                if ( m_bone_ids[n] >= 0 )
                {
                        const mesh_node_data* node = m_node_data->get_node(n);
                        nv::mat4 node_mat( node->transform );

                        if ( node->data )
                        {
                                node_mat = node->data->get_matrix( anim_time );
                        }

                        sint16 bone_id = m_bone_ids[n];
                        data[ bone_id ] = node_mat * m_offsets[ bone_id ];
                }
}

void nv::skeletal_animation_entry_gpu::prepare( const mesh_nodes_data* bones )
{
        if ( m_prepared ) return;
        std::unordered_map< std::string, nv::uint16 > bone_names;
        m_offsets = new mat4[ bones->get_count() ];
        for ( nv::uint16 bi = 0; bi < bones->get_count(); ++bi )
        {
                const mesh_node_data* bone = bones->get_node(bi);
                bone_names[ bone->name ] = bi;
                m_offsets[bi] = bone->transform;
        }

        for ( uint32 n = 0; n < m_node_data->get_count(); ++n )
        {
                const mesh_node_data* node = m_node_data->get_node(n);
                sint16 bone_id = -1;

                auto bi = bone_names.find( node->name );
                if ( bi != bone_names.end() )
                {
                        bone_id = bi->second;
                }
                m_bone_ids[n] = bone_id;
        }
        m_prepared = true;
}

void nv::skeletal_animation_entry_gpu::animate_rec( mat4* data, float time, uint32 node_id, const mat4& parent_mat ) const
{
        // TODO: fix transforms, which are now embedded,
        //       see note in assimp_loader.cc:load_node
        const mesh_node_data* node = m_node_data->get_node( node_id );
        mat4 node_mat( node->transform );

        if ( node->data )
        {
                node_mat = node->data->get_matrix( time );
        }

        mat4 global_mat = parent_mat * node_mat;

        sint16 bone_id = m_bone_ids[ node_id ];
        if ( bone_id >= 0 )
        {
                data[ bone_id ] = global_mat * m_offsets[ bone_id ];
        }

        for ( auto child : m_children[ node_id ] )
        {
                animate_rec( data, time, child, global_mat );
        }
}

nv::skeletal_animation_entry_gpu::~skeletal_animation_entry_gpu()
{
        delete[] m_offsets;
        delete[] m_children;
        delete[] m_bone_ids;
}

nv::skeletal_mesh_gpu::skeletal_mesh_gpu( context* a_context, const mesh_data* a_mesh, const mesh_nodes_data* a_bone_data )
        : skeletal_mesh( a_context ), m_bone_data( a_bone_data ), m_transform( nullptr )
{
        m_va          = a_context->create_vertex_array( a_mesh, nv::STATIC_DRAW );
        m_index_count = a_mesh->get_count();
        if ( m_bone_data )
        {
                m_transform = new mat4[ m_bone_data->get_count() ];
        }
}

void nv::skeletal_mesh_gpu::update_animation( animation_entry* a_anim, uint32 a_anim_time )
{
        if ( m_bone_data && a_anim )
        {
                skeletal_animation_entry_gpu * anim = (skeletal_animation_entry_gpu*)a_anim;
                anim->prepare( m_bone_data );
                anim->update_skeleton( m_transform, a_anim_time );
        }
}

void nv::skeletal_mesh_gpu::update( program a_program )
{
        if ( m_bone_data )
                m_context->get_device()->set_opt_uniform_array( a_program, "nv_m_bones", m_transform, m_bone_data->get_count() );
}

nv::transform nv::skeletal_mesh_gpu::get_node_transform( uint32 node_id ) const
{
        if ( node_id == 0 ) return transform();
        return transform( m_transform[ node_id ] );
}

nv::mat4 nv::skeletal_mesh_gpu::get_node_matrix( uint32 node_id ) const
{
        return m_transform[ node_id ];
}