Cómo: Mostrar y seleccionar mallas
Actualización: noviembre 2007
Puede crear y mostrar una matriz de mallas para que cuando se elija una malla (se puntee) en el dispositivo, cambie de color.
.gif "Nota") Nota: |
|---|
Las aplicaciones móviles Direct3D administradas requieren el software de Windows Mobile versión 5.0 para dispositivos Pocket PC y Smartphone. Vea Recursos externos de .NET Compact Framework para obtener información sobre el software de Windows Mobile y los SDK. |
El formulario de este ejemplo de código contiene los objetos siguientes:
Objeto Mesh para la malla activa.
Matriz de nueve objetos Mesh de distintos colores entre los que se puede escoger.
Estructura Vector3 que define las ubicaciones de la malla.
Dos estructuras Vector3 que definen el cuadro de límite.
Objeto Device.
El constructor de formularios especifica la configuración de la propiedad PresentationParameters del dispositivo, crea el objeto Device, agrega el controlador de eventos OnDeviceReset al evento DeviceReset del dispositivo y, a continuación, llama al método OnDeviceReset para empezar a crear las mallas. La tabla siguiente describe los métodos que representan las mallas y habilitan la interacción con el usuario.
Método |
Acciones |
|---|---|
OnDeviceReset |
Crea las mallas, los coloca en las ubicaciones del cuadro de límite y define las matrices de transformación. |
OnPaint |
Comienza la escena, dibuja las mallas y finaliza la escena. |
OnMouseDown |
Muestra la selección de una malla mediante una técnica que crea un radio a través del espacio 3D lógico y realiza una intersección entre el cuadro y el radio. El radio se representa presionando el lápiz óptico mientras se desplaza por el espacio 3D. El cuadro representa un rectángulo de selección alrededor del objeto 3D. Si los dos se intersecan, el usuario ha hecho clic en una ubicación que contiene el objeto 3D. |
Ejemplo
El ejemplo de código siguiente proporciona un formulario completo. Muestra objetos Mesh de distintos colores entre los que se pueden elegir. Cuando se elige una malla, cambia su color.
Imports System
Imports System.Drawing
Imports System.Windows.Forms
Imports Microsoft.WindowsMobile.DirectX
Imports Microsoft.WindowsMobile.DirectX.Direct3D
Imports Microsoft.VisualBasic
Class MeshPickingHowto
Inherits Form
Private Const numberOfMeshes As Integer = 9
Private meshes() As Mesh
Private meshColors() As Color = {Color.Green, Color.Orange, Color.Purple, Color.Pink, Color.Violet, Color.Blue, Color.Yellow, Color.Brown, Color.Aquamarine}
Private meshLocations() As Vector3
Private meshBoundingBoxMinValues() As Vector3
Private meshBoundingBoxMaxValues() As Vector3
Private activeMesh As Mesh
Private device As Device
Public Sub New()
Dim present As PresentParameters
Me.Text = "Mesh Picking"
' Enable the form to be closed.
' This is required so that Hwnd of the form changes.
Me.MinimizeBox = False
present = New PresentParameters()
present.Windowed = True
present.AutoDepthStencilFormat = DepthFormat.D16
present.EnableAutoDepthStencil = True
present.SwapEffect = SwapEffect.Discard
device = New Device(0, DeviceType.Default, Me, CreateFlags.None, present)
AddHandler device.DeviceReset, AddressOf OnDeviceReset
OnDeviceReset(Nothing, EventArgs.Empty)
End Sub
Private Sub OnDeviceReset(ByVal sender As Object, ByVal e As EventArgs)
' Meshes must be recreated whenever the device
' is reset, no matter which pool they are created in.
meshes = New Mesh(numberOfMeshes) {}
meshLocations = New Vector3(numberOfMeshes) {}
meshBoundingBoxMinValues = New Vector3(numberOfMeshes) {}
meshBoundingBoxMaxValues = New Vector3(numberOfMeshes) {}
activeMesh = Nothing
' Create several meshes and associated data.
Dim i As Integer
For i = 0 To numberOfMeshes
Dim vertexData As GraphicsStream
meshes(i) = Mesh.Box(device, 1F, 1F, 1F)
' Arrange the boxes in a grid, with each
' successive box farther in the distance.
meshLocations(i) = New Vector3((i Mod 3) * 2 - 2, i / 3 * 2 - 2, i)
' Compute the bounding box for a mesh.
Dim description As VertexBufferDescription = meshes(i).VertexBuffer.Description
vertexData = meshes(i).VertexBuffer.Lock(0, 0, LockFlags.ReadOnly)
Geometry.ComputeBoundingBox(vertexData, meshes(i).NumberVertices, description.VertexFormat, meshBoundingBoxMinValues(i), meshBoundingBoxMaxValues(i))
meshes(i).VertexBuffer.Unlock()
Next i
' Set the transformation matrices.
device.Transform.Projection = Matrix.PerspectiveFovRH(System.Convert.ToSingle(Math.PI) / 4F, System.Convert.ToSingle(Me.ClientSize.Width) / System.Convert.ToSingle(Me.ClientSize.Height), 0.001F, 40)
device.Transform.View = Matrix.LookAtRH(New Vector3(0, 2, - 7), New Vector3(0, 0, 0), New Vector3(0, 1, 0))
device.RenderState.Ambient = Color.White
End Sub
Protected Overrides Sub OnPaintBackground(ByVal e As PaintEventArgs)
' Do nothing.
End Sub
Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
Dim material As New Material()
' Begin the scene and clear the back buffer to black.
device.BeginScene()
device.Clear(ClearFlags.Target Or ClearFlags.ZBuffer, Color.Black, 1F, 0)
' Draw each mesh to the screen.
' The active mesh is drawn in red.
Dim i As Integer
For i = 0 To numberOfMeshes
If activeMesh Is meshes(i) Then
material.Ambient = Color.Red
Else
material.Ambient = meshColors(i)
End If
device.Transform.World = Matrix.Translation(meshLocations(i))
device.Material = material
meshes(i).DrawSubset(0)
Next i
' Finish the scene and present it on the screen.
device.EndScene()
device.Present()
End Sub
' This method demonstrates picking.
Protected Overrides Sub OnMouseDown(ByVal e As MouseEventArgs)
' The technique used here is to create a ray through the entire
' logical 3-D space, and then perform an intersection test
' for the bounding box and ray.
Dim i As Integer
For i = 0 To numberOfMeshes
Dim nearVector As New Vector3(e.X, e.Y, 0)
Dim farVector As New Vector3(e.X, e.Y, 1)
' Create ray.
nearVector.Unproject(device.Viewport, device.Transform.Projection, device.Transform.View, Matrix.Translation(meshLocations(i)))
farVector.Unproject(device.Viewport, device.Transform.Projection, device.Transform.View, Matrix.Translation(meshLocations(i)))
farVector.Subtract(nearVector)
' Perform intersection test for the bounding box and ray.
If Geometry.BoxBoundProbe(meshBoundingBoxMinValues(i), meshBoundingBoxMaxValues(i), nearVector, farVector) Then
' Perform operation on detection of click on mesh object.
' In this case, you designate the mesh as the active
' mesh and invalidate the window so that it is redrawn.
activeMesh = meshes(i)
Me.Invalidate()
Exit For
End If
Next i
End Sub
Shared Sub Main()
Application.Run(New MeshPickingHowto())
End Sub
End Class
using System;
using System.Drawing;
using System.Windows.Forms;
using Microsoft.WindowsMobile.DirectX;
using Microsoft.WindowsMobile.DirectX.Direct3D;
namespace MeshPick
{
class MeshPickingHowto : Form
{
const int numberOfMeshes = 9;
Mesh [] meshes;
Color [] meshColors = new Color [] { Color.Green, Color.Orange,
Color.Purple, Color.Pink, Color.Violet, Color.Blue, Color.Yellow,
Color.Brown, Color.Aquamarine };
Vector3 [] meshLocations;
Vector3 [] meshBoundingBoxMinValues;
Vector3 [] meshBoundingBoxMaxValues;
Mesh activeMesh;
Device device;
public MeshPickingHowto()
{
PresentParameters present;
this.Text = "Mesh Picking";
// Enable the form to be closed.
// This is required so that Hwnd of the form changes.
this.MinimizeBox = false;
present = new PresentParameters();
present.Windowed = true;
present.AutoDepthStencilFormat = DepthFormat.D16;
present.EnableAutoDepthStencil = true;
present.SwapEffect = SwapEffect.Discard;
device = new Device(0, DeviceType.Default, this,
CreateFlags.None, present);
device.DeviceReset += new EventHandler(OnDeviceReset);
OnDeviceReset(null, EventArgs.Empty);
}
private void OnDeviceReset(object sender, EventArgs e)
{
// Meshes must be recreated whenever the device
// is reset, no matter which pool they are created in.
meshes = new Mesh[numberOfMeshes];
meshLocations = new Vector3[numberOfMeshes];
meshBoundingBoxMinValues = new Vector3[numberOfMeshes];
meshBoundingBoxMaxValues = new Vector3[numberOfMeshes];
activeMesh = null;
// Create several meshes and associated data.
for (int i = 0; i < numberOfMeshes; i++)
{
GraphicsStream vertexData;
meshes[i] = Mesh.Box(device, 1.0f, 1.0f, 1.0f);
// Arrange the boxes in a grid, with each
// successive box farther in the distance.
meshLocations[i] = new Vector3(((i % 3) * 2) - 2,
((i / 3) * 2) - 2, i);
// Compute the bounding box for a mesh.
VertexBufferDescription description =
meshes[i].VertexBuffer.Description;
vertexData = meshes[i].VertexBuffer.Lock
(0, 0, LockFlags.ReadOnly);
Geometry.ComputeBoundingBox(vertexData,
meshes[i].NumberVertices,description.VertexFormat,
out meshBoundingBoxMinValues[i],
out meshBoundingBoxMaxValues[i]);
meshes[i].VertexBuffer.Unlock();
}
// Set the transformation matrices.
device.Transform.Projection = Matrix.PerspectiveFovRH(
(float)Math.PI/4.0F,
(float)this.ClientSize.Width / (float)this.ClientSize.Height,
0.001f, 40);
device.Transform.View = Matrix.LookAtRH(new Vector3(0, 2, -7),
new Vector3(0, 0, 0), new Vector3(0, 1, 0));
device.RenderState.Ambient = Color.White;
}
protected override void OnPaintBackground(PaintEventArgs e)
{
// Do nothing.
}
protected override void OnPaint(PaintEventArgs e)
{
Material material = new Material();
// Begin the scene and clear the back buffer to black.
device.BeginScene();
device.Clear(ClearFlags.Target | ClearFlags.ZBuffer,
Color.Black, 1.0f, 0);
// Draw each mesh to the screen.
// The active mesh is drawn in red.
for (int i = 0; i < numberOfMeshes; i++)
{
if (activeMesh == meshes[i])
material.Ambient = Color.Red;
else
material.Ambient = meshColors[i];
device.Transform.World = Matrix.Translation(meshLocations[i]);
device.Material = material;
meshes[i].DrawSubset(0);
}
// Finish the scene and present it on the screen.
device.EndScene();
device.Present();
}
// This method demonstrates picking.
protected override void OnMouseDown(MouseEventArgs e)
{
// The technique used here is to create a ray through the entire
// logical 3-D space, and then perform an intersection test
// for the bounding box and ray.
for (int i = 0; i < numberOfMeshes; i++)
{
Vector3 nearVector = new Vector3(e.X, e.Y, 0);
Vector3 farVector = new Vector3(e.X, e.Y, 1);
// Create ray.
nearVector.Unproject(device.Viewport,
device.Transform.Projection,
device.Transform.View,
Matrix.Translation(meshLocations[i]));
farVector.Unproject(device.Viewport,
device.Transform.Projection,
device.Transform.View,
Matrix.Translation(meshLocations[i]));
farVector.Subtract(nearVector);
// Perform intersection test for the bounding box and ray.
if (Geometry.BoxBoundProbe(meshBoundingBoxMinValues[i],
meshBoundingBoxMaxValues[i], nearVector, farVector))
{
// Perform operation on detection of click on mesh object.
// In this case, you designate the mesh as the active
// mesh and invalidate the window so that it is redrawn.
activeMesh = meshes[i];
this.Invalidate();
break;
}
}
}
static void Main()
{
Application.Run(new MeshPickingHowto());
}
}
}
Compilar el código
Para este ejemplo se requieren referencias a los siguientes espacios de nombres:
Vea también
Conceptos
.Temas "Cómo..." de .NET Compact Framework