//Generates the background texture
public void CreateBackgroundTexture(GraphicsDevice device, SpriteBatch batch, int width, int height)
{
Texture = new RenderTarget2D(device, width, height);
List <LSystem.Rule> rules = new List <LSystem.Rule>();
rules.Add(new LSystem.Rule("F", "1FF-[2-F+F-F]+[2+F-F+F]")); //basic tree
defaultSystem = new LSystem("F", 10, 22, rules);
turtle = new Turtle(device, batch, new Vector2(200, 640), -90, Color.White, palette);
device.SetRenderTarget(Texture);
device.Clear(palette[0]);
batch.Begin();
RenderTarget2D target = new RenderTarget2D(device, width, height);
//Pregenerate trees
List <LSystem> trees = new List <LSystem>();
for (int i = 0; i < 6; ++i)
{
var currentSystem = new LSystem(defaultSystem);
currentSystem.Iterate(i);
trees.Add(currentSystem);
}
//create clouds
int count = Math.Max(1, AlgorithmHelper.GetRandom(width / 512, width / 96));
int nextX = AlgorithmHelper.GetRandom(0, width / count);
int nextY;
for (int i = 1; i < count; ++i)
{
nextY = AlgorithmHelper.GetRandom(0, 100);
int w = AlgorithmHelper.GetRandom(32, 512);
int h = AlgorithmHelper.GetRandom(32, 128);
Texture2D cloud = new Texture2D(device, w, h);
GraphicsHelper.FillRectangle(cloud, palette[7]);
GraphicsHelper.OutlineRectangle(cloud, ColorHelper.ChangeColorBrightness(palette[5], -0.2f), 8);
batch.Draw(cloud, new Rectangle(nextX, nextY, w, h), Color.White);
nextX += AlgorithmHelper.GetRandom(0, (int)(w * 1.5));
if (nextX > width)
{
nextX -= AlgorithmHelper.GetRandom(w, (int)(width / 1.5));
}
}
count = Math.Max(1, AlgorithmHelper.GetRandom(width / 256, width / 64));
nextX = AlgorithmHelper.GetRandom(0, width / count);
for (int i = 0; i < count; ++i)
{
int size = AlgorithmHelper.GetRandom(1, trees.Count - 1);
while (nextX + 100 * size > width)
{
--size;
}
if (size == trees.Count - 2 && AlgorithmHelper.GetRandom(0, 10) > 6)
{
size = size + 1;
}
if (size < 0)
{
break;
}
if (i == 0 && nextX < size * 20)
{
nextX = size * 20;
}
var currentSystem = trees[size];
turtle.SetDefaults(new Vector2(nextX, 640), -90);
turtle.DrawSystem(currentSystem, target);
nextX += 50 * size;
}
batch.Draw(target, new Rectangle(0, 0, width, height), Color.White);
batch.End();
device.SetRenderTarget(null);
}
//Draws the whole L-System to an existing RenderTarget2D
public RenderTarget2D DrawSystem(LSystem System, RenderTarget2D target)
{
time = new Stack <Moment>();
now = new Moment(defaultMoment);
Random r = new Random((int)DateTime.Now.Ticks);
foreach (char c in System.State)
{
if (c == 'F' || c == 'G' || c == 'H')
{
MoveTurtle(System.Step, target);
}
else if (c == '0')
{
currentColor = palette[2];
}
else if (c == '1')
{
currentColor = palette[3];
}
else if (c == '2')
{
currentColor = palette[4];
}
else if (c == '3')
{
currentColor = palette[5];
}
else if (c == '4')
{
currentColor = palette[6];
}
else if (c == '+')
{
now.angle -= System.Angle;
}
else if (c == '-')
{
now.angle += System.Angle;
}
else if (c == '[')
{
time.Push(new Moment(now));
}
else if (c == ']')
{
now = time.Pop();
}
}
return(target);
}
