season.c

利用VC++和OpenGVS结合编的一个关于火车运行的三维模拟程序。是OpenGVS三维初学者的应该参考的好范例。

/****************************************************************************
*
*  season.c -- 
*
*       Season management (scene changes basically)
*
*****************************************************************************/
#include <g_sys.h>
#include <g_key.h>
#include <g_consts.h>
#include "train.h"


/*************************************************************************** 
*
*  season_change
*
*	Called discretely - when it is time to switch from one season
*	to another as specified by the caller
*
****************************************************************************/
void season_change( Season newseason )
{
    static GV_Obi skydome = NULL;
    static GV_Obi train_town = NULL;
    static GV_Obi summer_time = NULL;
    static GV_Obi autumn_time = NULL;
    static GV_Obi winter_time = NULL;

    /* Save some handles */
    if( !train_town )
    {
        GV_obi_inq_by_name( "TRAIN_TOWN", &train_town );
	GV_obi_inq_by_name_relative( train_town, ".../summer", &summer_time);
	GV_obi_inq_by_name_relative( train_town, ".../autumn", &autumn_time);
	GV_obi_inq_by_name_relative( train_town, ".../winter", &winter_time);
        GV_obi_inq_by_name( "SKYDOME", &skydome );
    }

    /********************** Season control ******************************/
    if( newseason == SEASON_SUMMER )
    {
	GV_obi_set_state( summer_time, G_ON );
	GV_obi_set_state( autumn_time, G_OFF );
	GV_obi_set_state( winter_time, G_OFF );
	GV_obi_set_state( skydome, G_ON );
    }
    else if( newseason == SEASON_AUTUMN )
    {
	GV_obi_set_state( summer_time, G_OFF );
	GV_obi_set_state( autumn_time, G_ON );
	GV_obi_set_state( winter_time, G_OFF );
	GV_obi_set_state( skydome, G_OFF );
    }
    else if( newseason == SEASON_WINTER )
    {
	GV_obi_set_state( summer_time, G_OFF );
	GV_obi_set_state( autumn_time, G_OFF );
	GV_obi_set_state( winter_time, G_ON );
	GV_obi_set_state( skydome, G_OFF );
    }
}