/// <summary>
/// Initialize the sample.
/// </summary>
protected override void Initialize()
{
// create a default world and matrix
meshRotation = Matrix.Identity;
// create the mesh array
sampleMeshes = new Model[5];
// set up the sample camera
camera = new SampleArcBallCamera(SampleArcBallCameraMode.RollConstrained);
camera.Distance = 12;
// orbit the camera so we're looking down the z=-1 axis,
// at the "front" of the object
camera.OrbitRight(MathHelper.Pi);
// orbit up a bit for perspective
camera.OrbitUp(.2f);
//set up a ring of meshes
meshWorlds = new Matrix[8];
for (int i = 0; i < 8; i++)
{
float theta = MathHelper.TwoPi * ((float)i / 8f);
meshWorlds[i] = Matrix.CreateTranslation(
5f * (float)Math.Sin(theta), 0, 5f * (float)Math.Cos(theta));
}
// set the initial material assignments to the geometry
materialRotation = 2;
// stretch the cube out to represent a "floor"
// that will help visualize the light radii
floorWorld = Matrix.CreateScale(30f, 1f, 30f) *
Matrix.CreateTranslation(0, -2.2f, 0);
lightMeshWorld = Matrix.CreateScale(.2f);
base.Initialize();
}
private void HandleInput(GameTime gameTime, GamePadState gpState,
KeyboardState kbState)
{
float elapsedTime = (float)gameTime.ElapsedGameTime.TotalSeconds;
// handle input for rotating the materials
if (((gpState.Buttons.X == ButtonState.Pressed) &&
(lastGpState.Buttons.X == ButtonState.Released)) ||
(kbState.IsKeyDown(Keys.Tab) && lastKbState.IsKeyUp(Keys.Tab)))
{
// switch the active mesh
materialRotation = (materialRotation + 1) % materials.Length;
}
// handle input for adding lights to the scene
if (((gpState.Buttons.RightShoulder == ButtonState.Pressed) &&
(lastGpState.Buttons.RightShoulder == ButtonState.Released)) ||
(kbState.IsKeyDown(Keys.Add) && lastKbState.IsKeyUp(Keys.Add)))
{
numLights = ((numLights) % (maxLights)) + 1;
}
// handle input for removing lights from the scene
if (((gpState.Buttons.LeftShoulder == ButtonState.Pressed) &&
(lastGpState.Buttons.LeftShoulder == ButtonState.Released)) ||
(kbState.IsKeyDown(Keys.Subtract) &&
lastKbState.IsKeyUp(Keys.Subtract)))
{
numLights = (numLights - 1);
if (numLights < 1)
{
numLights = maxLights;
}
}
// handle input for adding lights to the scene
if (((gpState.DPad.Up == ButtonState.Pressed) &&
(lastGpState.DPad.Up == ButtonState.Released)) ||
(kbState.IsKeyDown(Keys.P) && lastKbState.IsKeyUp(Keys.P)))
{
numLightsPerPass = ((numLightsPerPass) % (maxLightsPerPass)) + 1;
lightingEffect.Parameters["numLightsPerPass"].SetValue(numLightsPerPass);
}
// handle input for generating new values for the lights
if (((gpState.Buttons.Y == ButtonState.Pressed) &&
(lastGpState.Buttons.Y == ButtonState.Released)) ||
(kbState.IsKeyDown(Keys.Space) && lastKbState.IsKeyUp(Keys.Space)))
{
GenerateRandomLights();
}
// handle mesh rotation inputs
float dx =
SampleArcBallCamera.ReadKeyboardAxis(kbState, Keys.Left, Keys.Right) +
gpState.ThumbSticks.Left.X;
float dy =
SampleArcBallCamera.ReadKeyboardAxis(kbState, Keys.Down, Keys.Up) +
gpState.ThumbSticks.Left.Y;
// apply mesh rotation from inputs
if (dx != 0)
{
meshRotation *= Matrix.CreateFromAxisAngle(camera.Up,
elapsedTime * dx);
}
if (dy != 0)
{
meshRotation *= Matrix.CreateFromAxisAngle(camera.Right,
elapsedTime * -dy);
}
// handle the light rotation inputs
float lightRotation =
SampleArcBallCamera.ReadKeyboardAxis(kbState, Keys.PageUp,
Keys.PageDown) + gpState.Triggers.Right - gpState.Triggers.Left;
if (lightRotation != 0)
{
Matrix rotation = Matrix.CreateRotationY(lightRotation * elapsedTime);
foreach (PointLight light in lights)
{
// rotate all of the lights by transforming their positions
light.Position = Vector4.Transform(light.Position, rotation);
}
}
}
