/// <summary>
/// This is called when the game should draw itself.
/// </summary>
protected override void Draw(GameTime gameTime)
{
GraphicsDevice device = graphics.GraphicsDevice;
device.Clear(Color.CornflowerBlue);
device.BlendState = BlendState.AlphaBlend;
// Compute camera matrices.
Matrix view = Matrix.CreateLookAt(cameraPosition,
cameraPosition + cameraForward,
cameraUp);
Matrix projection = Matrix.CreatePerspectiveFieldOfView(1, device.Viewport.AspectRatio,
1, 100000);
// Draw the checkered ground polygon.
Matrix groundTransform = Matrix.CreateScale(20000) *
Matrix.CreateRotationX(MathHelper.PiOver2);
quadDrawer.DrawQuad(checkerTexture, 32, groundTransform, view, projection);
// Draw the game entities.
cat.Draw(quadDrawer, cameraPosition, view, projection);
dog.Draw(quadDrawer, cameraPosition, view, projection);
base.Draw(gameTime);
}
/// <summary>
/// Draws the entity as a billboard sprite.
/// </summary>
public void Draw(QuadDrawer quadDrawer, Vector3 cameraPosition,
Matrix view, Matrix projection)
{
Matrix world = Matrix.CreateTranslation(0, 1, 0) *
Matrix.CreateScale(800) *
Matrix.CreateConstrainedBillboard(Position, cameraPosition,
Up, null, null);
quadDrawer.DrawQuad(Texture, 1, world, view, projection);
}
/// <summary>
/// Draws the entity as a billboard sprite.
/// </summary>
public void Draw(QuadDrawer quadDrawer, Vector3 cameraPosition,
Matrix view, Matrix projection)
{
Matrix world = Matrix.CreateTranslation(0, 1, 0) *
Matrix.CreateScale(800) *
Matrix.CreateConstrainedBillboard(Position, cameraPosition,
Up, null, null);
quadDrawer.DrawQuad(Texture, 1, world, view, projection);
}
