m3gmidlet.java

来自「3D手机游戏开发实例源代码」· Java 代码 · 共 213 行

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.m3g.*;
public class M3GMIDlet extends MIDlet 
{

  private static final String MODEL_FN = "/pogoroo.m3g";				//字符串指定文件名
   
  private float trans[] = new float[16];
  private Transform modelTransform = new Transform();
  
private Group modelGroup = null;     // top-level Group node for the model
private boolean foundGroup  = false;   // Group node found during the search?
private boolean isSceneRoot = true;  // is found Group node the root of the scene graph?

 
  
  /**
   * Starts application and shows the list of samples. The user can 
   * select a sample for execution and return to the selection screen.
   */
  public void startApp()
  {
  System.out.println("Loading model from " + MODEL_FN);			//控制台输出加载文件信息
  Object3D[] parts = null;								//Object3D数组用来保存场景信息
  try {
    parts = Loader.load(MODEL_FN); 					//根据MODEL_FN文件名加载文件
  }catch (Exception e) 									//捕捉异常
  { e.printStackTrace(); } 									//输出异常信息
  parseObjects(parts, "", null, 0); 								//解析对象数组
  destroyApp(true); 										//结束程序
  notifyDestroyed();

  }
    // ---------------- parse model ----------------

  private void parseObjects(Object3D[] parts, String section, 
                                       Object3D parent, int level)
  /* Examine each of the objects in the parts[] array. Print each
     object's class name and user ID. */
  {
    String name, subsection;
    for (int i=0; i < parts.length; i++) {
      name = parts[i].getClass().getName();
      subsection = section + (i+1) + ".";
      printlnIndent(subsection + " " + name + ", ID: " + 
                                  parts[i].getUserID(), level);
      parseNode(parts[i], name, parent, level);
      parseRefs(parts[i], subsection, level+1);
    }
  }  // end of parseObjects()


  private void parseNode(Object3D part, String name, 
                                         Object3D parent, int level)
  /* Store the top-level Group node in modelGroup.
     Examine Group, VertexBuffer, and Material nodes in more detail. */
  {
    if (name.endsWith("Group")) {
      storeGroup((Group) part, parent, level);
      parseGroup((Group) part, level);
    }
    else if (name.endsWith("VertexBuffer"))
      parseVertexBuffer((VertexBuffer) part, level);
    else if (name.endsWith("Material"))
      parseMaterial( (Material) part, level);
  }  // end of parseNode()


  private void storeGroup(Group g, Object3D parent, int level)
  /* Store the found Group node in modelGroup, and attempt to
     detach it from its parent if it isn't the root node of the 
     scene. */
  {
    if (!foundGroup) {   // if not already found a Group node
      modelGroup = g;
      System.out.println("modelGroup assigned Group with ID " + g.getUserID() +
                         "; at level " + level);
      foundGroup = true;
      if (level != 0) {   // the Group is not the root node
        isSceneRoot = false;
        if (parent instanceof Group) {
          Group gPar = (Group) parent;
          gPar.removeChild(modelGroup);
          System.out.println("Detached modelGroup from parent with ID " +
                                      gPar.getUserID() );
        }
        else {
          System.out.println("Could not detach modelGroup; set to null");
          modelGroup = null;   // since cannot attach it to our scene
        }
      }
    }
  }  // end of storeGroup()


  private void parseGroup(Group g, int level)
  // Print the the composite transform matrix for the Group
  {
    g.getCompositeTransform(modelTransform);
    modelTransform.get(trans);

    for(int i=0; i < 16; i= i+4)
      printlnIndent( round2dp(trans[i]) + " " + 
                     round2dp(trans[i+1]) + " " +
                     round2dp(trans[i+2]) + " " + 
                     round2dp(trans[i+3]), level);
  }  // end of parseGroup()


  private float round2dp(float num)
  // round num to 2 decimal places
  {  return ((int)((num+0.005)*100.0f))/100.0f;  }



  private void parseVertexBuffer(VertexBuffer vb, int level)
  /* Print information about the VertexBuffer's contents: the
     positions, colours, normals, and number of textures. */
  {
    float[] scaleBias = new float[4];
    VertexArray va = vb.getPositions(scaleBias);

    printlnIndent("Positions: " + (va != null) + 
                  ";  No. Coords: " + (vb.getVertexCount()/3), level);
    if (va != null)
      printlnIndent("Posn ID: " + va.getUserID() + 
                    ";  User Object: " + (va.getUserObject() != null), level);

    printlnIndent("Scale/Bias: " + round2dp(scaleBias[0]) + " " +
                                   round2dp(scaleBias[1]) + " " +
                                   round2dp(scaleBias[2]) + " " +
                                   round2dp(scaleBias[3]), level);
    int texCount = 0;
    while (true) {
      if (vb.getTexCoords(texCount, scaleBias) == null)
        break;
      texCount++;
    }

    printlnIndent("Colours: " + (vb.getColors() != null) + 
                  ";  Normals: " + (vb.getNormals() != null) +
                  ";  No. of textures: " + texCount, level);
  }  // end of parseVertexBuffer()


  private void parseMaterial(Material m, int level)
  /* Show colour and shininess info for the material. */
  {
    int ambColour = m.getColor(Material.AMBIENT);
    int diffColour = m.getColor(Material.DIFFUSE);
    int emisColour = m.getColor(Material.EMISSIVE);
    int specColour = m.getColor(Material.SPECULAR);

    printlnIndent("Colours: " +  ambColour + ", " + diffColour + ", " +
                                emisColour + ", " + specColour + ", " +
                                m.getShininess(), level);

    printlnIndent("Colours in Hex: " + Integer.toHexString(ambColour) + ", " + 
                                       Integer.toHexString(diffColour) + ", " +
                                       Integer.toHexString(emisColour) + ", " + 
                                       Integer.toHexString(specColour), level);

  }  // end of parseMaterial()



  private void parseRefs(Object3D obj, String section, int level)
  /* Examine all the references connected to obj. */
  {
    int numRefs = obj.getReferences(null);
    if (numRefs > 0) {
      Object3D[] parts = new Object3D[numRefs];
      obj.getReferences(parts);
      parseObjects(parts, section, obj, level);
    }
  }  // end of parseRefs()


  private void printlnIndent(String msg, int level)
  // indent msg by level*2 spaces
  {

      for(int i=0; i < level; i++)
        System.out.print("  ");   // 2 spaces
      System.out.println(msg);

  }  // end of printlnIndent()
  /**
   * Not used.
   */
  public void pauseApp()
  {
  }
  
  /**
   * Not used.
   */
  public void destroyApp(boolean unconditional)
  {
  }
  
  /**
   * Receives the command actions from the selection screen as well as
   * the sample screens.
   *
   * @param command command
   * @param displayable source of the command
   */

}