Develop Reference

How to modify perlin noise to generate a simple shape?

I am working on a project in Unity that needs to generate some simple 3D Mountains/Hills. Since my requirements are to create a "simple" shape, I don't seem to find an answer and I thought maybe I can get some help from here. Anyways, this is a normal output from perlin noise, although it's smooth, the output is still complicated with lots of hills/mountains. I am looking for something like this . I need to be sure that I won't have any height around the borders of the Output Image. I think you've got the idea. Have a Great Day!
Here is the code I am using right now from an online tutorial:
using UnityEngine;
public class PerlinNoise : MonoBehaviour
{
private static int width = 256;
private static int height = 128;
public float scale = 20f;
public float offsetX = 100f;
public float offsetY = 100f;
private int xcont = 0, ycont = 0;
public float[,] array = new float[width,height];
private void Start()
{
offsetX = Random.Range(0f, 99999f);
offsetY = Random.Range(0f, 99999f);
}
void Update()
{
Renderer renderer = GetComponent<Renderer>();
renderer.material.mainTexture = GenerateTexture();
}
Texture2D GenerateTexture()
{
Texture2D texture = new Texture2D(width, height);
//GENERATE A PERLIN NOISE MAP FOR THE TEXTURE
for(int x=0;x<width;x++)
{
for(int y=0;y<height;y++)
{
Color color = CalculateColor(x,y);
texture.SetPixel(x, y, color);
}
}
texture.Apply();
return texture;
}
Color CalculateColor(int x, int y)
{
float xCoord = (float)x / width * scale + offsetX;
float yCoord = (float)y / height * scale + offsetY;
float sample = Mathf.PerlinNoise(xCoord,yCoord);
if (xcont == width - 1)
{
xcont = 0;
ycont++;
}
else xcont++;
if (ycont == height - 1 ) ycont = 0;
array[xcont,ycont] = sample;
return new Color(sample, sample, sample);
}
}

You can filter that texture down using cellular automata.
This playlist might help you understand how and when Perlin Noise is used for map generation: https://www.youtube.com/playlist?list=PLFt_AvWsXl0eZgMK_DT5_biRkWXftAOf9

How to determine scale to increase sprite width to screen width

I am trying to achieve something similar to How to increase (animate) the width of the square on both ends in Unity. How can I determine the scale by which to increase the width (of the sprite) for it to fill the whole screen width?
UPDATE
Below is the Swift code for I implemented for expanding the sprite width to take the full screen width:
func expandEnemy () {
spritePosBeforeScaleX = CGPointMake((enemy?.sprite.position.x)!, (enemy?.sprite.anchorPoint.y)!)
enemy?.sprite.anchorPoint = CGPointMake((enemy?.sprite.position.x)! / self.size.width, (enemy?.sprite.anchorPoint.y)!)
let enemyScalingAction = SKAction.scaleXTo(self.size.width / (enemy?.sprite.size.width)!, duration: 1.0)
enemy!.sprite.runAction(enemyScalingAction)
delay(0.1)
{
center = CGPointMake(enemy!.sprite.size.width / 2 - (enemy!.sprite.size.width * enemy!.sprite.anchorPoint.x), enemy!.sprite.size.height / 2 - (enemy!.sprite.size.height * enemy!.sprite.anchorPoint.y))
enemy!.sprite.physicsBody = SKPhysicsBody(rectangleOfSize: enemy!.sprite.size, center: center)
}
}

It all depends on the aspect ratio of the screen and the size of the object with the SpriteRenderer. You need to scale up the gameobject that holds the spriterenderer by a factor where you take these into consideration.
[ExecuteInEditMode]
public class SpriteToScreen : MonoBehaviour {
public float sprw = 256f;
public float sprh = 256f;
float unitspp = 100f;
public float scrw = 0f;
public float scrh = 0f;
public float aspect = 0f;
public float spr_aspect = 1f;
public float factorY = 0.017578125f;
public void Update(){
scrw = Screen.width;
scrh = Screen.height;
aspect = scrw / scrh;
unitspp = this.GetComponent<SpriteRenderer>().sprite.pixelsPerUnit;
sprw = this.GetComponent<SpriteRenderer>().sprite.bounds.size.x * unitspp;
sprh = this.GetComponent<SpriteRenderer>().sprite.bounds.size.y * unitspp;
spr_aspect = sprw / sprh;
this.transform.localScale = new Vector3( (1152f / sprh * aspect) / spr_aspect,
1152f / sprh,
1 );
}
}

You can scale Image of an UI in x-axis full screen. Just get the RectTransform then modify the sizeDelta property of it to the Screen size of the device or the size of the Canvas.
The function below can scale Unity UI Image in x, y or both x and y axis full screen. The Image to scale must be under Canvas. Assign a Sprite to the Source Image of the Image component the code below should work.
//Attach the UI Image to scacle in the Editor here
public GameObject image;
To Scale:
Scale in X-axis Full Screen in 3 seconds:
StartCoroutine(scaleToFullScreen(image, 0, 3f));
Scale in Y-axis Full Screen in 3 seconds:
StartCoroutine(scaleToFullScreen(image, 1, 3f));
Scale in X-axis AND Y-axis Full Screen in 3 seconds:
StartCoroutine(scaleToFullScreen(image, 2, 3f));
The Scale function:
bool isScaling = false;
IEnumerator scaleToFullScreen(GameObject imageToScale, int scaleType, float byTime)
{
if (isScaling)
{
yield break;
}
if (scaleType < 0 || scaleType > 2)
{
Debug.Log("Invalid ScaleType. Valid Scale Types X:0, Y:1, XandY:3");
yield break;
}
isScaling = true;
Canvas canvas = imageToScale.GetComponentInParent<Canvas>();
float x, y;
if (canvas != null)
{
x = canvas.pixelRect.width;
y = canvas.pixelRect.height;
}
else
{
x = Screen.width;
y = Screen.height;
}
RectTransform rect = imageToScale.GetComponent<RectTransform>();
if (rect == null)
{
rect = imageToScale.AddComponent<RectTransform>();
}
//Center the position of the image so that it will be resized equally
rect.anchoredPosition3D = new Vector3(0, 0, rect.anchoredPosition3D.z);
//The default Size
Vector2 originalScale = rect.sizeDelta;
//The new scale we want to scale texture to
Vector2 newScale = originalScale;
if (scaleType == 0)
{
newScale.x = x;
}
else if (scaleType == 1)
{
newScale.y = y;
}
else if (scaleType == 2)
{
newScale.x = x;
newScale.y = y;
}
float counter = 0;
while (counter < byTime)
{
counter += Time.deltaTime;
rect.sizeDelta = Vector2.Lerp(originalScale, newScale, counter / byTime);
yield return null;
}
isScaling = false;
}

XNA Parallaxing background wont show all the layers

Im playing around with the Platformer Starter Kit and so far I've added in horizontal and vertical "camera" movement and Im trying to add inn a parallaxing background. The problem is that after two background layers it stops showing the rest of them. Im very new to XNA and need a little help :). Heres a pic of the problem:
Heres the code. Please tell me if you need some more :)
Layer classes:
class Layer
{
public Texture2D[] Textures { get; private set; }
public float ScrollRate { get; private set; }
public Layer(ContentManager content, string basePath, float scrollRate)
{
// Assumes each layer only has 3 segments.
Textures = new Texture2D[3];
for (int i = 0; i < 3; ++i)
Textures[i] = content.Load<Texture2D>(basePath + "_" + i);
ScrollRate = scrollRate;
}
public void Draw(SpriteBatch spriteBatch, float cameraPosition, float cameraPositionYAxis)
{
// Assume each segment is the same width.
int segmentWidth = Textures[0].Width;
// Calculate which segments to draw and how much to offset them.
float x = cameraPosition * ScrollRate;
float y = ScrollRate;
int leftSegment = (int)Math.Floor(x / segmentWidth);
int rightSegment = leftSegment + 1;
x = (x / segmentWidth - leftSegment) * -segmentWidth;
spriteBatch.Draw(Textures[leftSegment % Textures.Length], new Vector2(x, -y), Color.White);
spriteBatch.Draw(Textures[rightSegment % Textures.Length], new Vector2(x + segmentWidth, -y), Color.White);
}
}
Heres the draw method in my Level.cs with my ScrollCamera (dont know if ScrollCamera has anything to do with it)
public void Draw(GameTime gameTime, SpriteBatch spriteBatch)
{
ScrollCamera(spriteBatch.GraphicsDevice.Viewport);
Matrix cameraTransformYAxis = Matrix.CreateTranslation(-cameraPosition, -cameraPositionYAxis, 0.0f);
spriteBatch.Begin(SpriteSortMode.Immediate, BlendState.AlphaBlend, SamplerState.LinearClamp,
DepthStencilState.Default, RasterizerState.CullCounterClockwise, null, cameraTransformYAxis);
//added this foreach loop
foreach (var layer in layers)
{
layer.Draw(spriteBatch, cameraPosition, cameraPositionYAxis);
}
DrawTiles(spriteBatch);
Player.Draw(gameTime, spriteBatch);
foreach (Enemy enemy in enemies)
{
enemy.Draw(gameTime, spriteBatch);
}
spriteBatch.End();
}
private void ScrollCamera(Viewport viewport)
{
#if ZUNE
const float ViewMargin = 0.4f;
#else
const float ViewMargin = 0.5f;
#endif
float marginWidth = viewport.Width * ViewMargin;
float marginLeft = cameraPosition + marginWidth;
float marginRight = cameraPosition + viewport.Width - marginWidth;
const float TopMargin = 0.4f;
const float BottomMargin = 0.4f;
float marginTop = cameraPositionYAxis + viewport.Height * TopMargin;
float marginBottom = cameraPositionYAxis + viewport.Height - viewport.Height * BottomMargin;
// float maxCameraPositionYOffset = Tile.Height * Height - viewport.Height;
float CameraMovement = 0.0f;
if (Player.Position.X < marginLeft)
CameraMovement = Player.Position.X - marginLeft;
else if (Player.Position.X > marginRight)
CameraMovement = Player.Position.X - marginRight;
//Aktualizuj przesuwanie ekranu, ale zapobiegnij wyjściu poza mape
float maxCameraPosition = Tile.Width * Width - viewport.Width;
cameraPosition = MathHelper.Clamp(cameraPosition + CameraMovement, 0.0f, maxCameraPosition);
float cameraMovementY = 0.0f;
if (Player.Position.Y < marginTop) //above the top margin
cameraMovementY = Player.Position.Y - marginTop;
else if (Player.Position.Y > marginBottom) //below the bottom margin
cameraMovementY = Player.Position.Y - marginBottom;
float maxCameraPositionYOffset = Tile.Height * Height - viewport.Height;
cameraPositionYAxis = MathHelper.Clamp(cameraPositionYAxis + cameraMovementY, 0.0f, maxCameraPositionYOffset);
}
And I think thats it. Please tell me if you need some more code :)

You want to use Linear Wrapping. There's an excellent blog post on it right here. This assumes of course that your texture tiles perfect. You just simply need to to set your linear wrapping mode, code example below:
// Use this one instead!
spriteBatch.Begin(SpriteSortMode.Deferred, null, SamplerState.LinearWrap, null, null);
spriteBatch.Draw(texture, position, new Rectangle(-scrollX, -scrollY, texture.Width, texture.Height), Color.White);
spriteBatch.End();

Light Rendering Results in Low FPS

I am currently developing a class for my XNA game whose rendering the lights on the image. At the time, i have made the source to draw my lightmap, however, the FPS is very low in my source. I know that it is brutally reduced upon looping through each pixel, however, I do not know any other way to get & set each pixel on my Texture in XNA but using the "For" statement?
Current Source:
public struct Light
{
public int Range;
public int Intensity;
public Color LightColor;
public Vector2 LightLocation;
public Light(int _Range, int _Intensity, Color _LightColor, Vector2 _LightLocation)
{
Range = _Range;
Intensity = _Intensity;
LightLocation = _LightLocation;
LightColor = _LightColor;
}
}
public class RenderClass
{
[System.Runtime.InteropServices.DllImport("User32.dll")]
public static extern bool MessageBox(IntPtr h, string S, string C, int a);
public static Texture2D RenderImage(Light[] LightLocations, Texture2D ScreenImage, Viewport v, bool ShadowBack = false)
{
Texture2D[] Images = new Texture2D[LightLocations.Count()];
int curCount = 0;
/*LOOP THROUGHT EACH LIGHT*/
foreach (Light LightLocation in LightLocations)
{
/*VARIABLES*/
Color LightColor = LightLocation.LightColor;
int Range = LightLocation.Range;
int Intensity = LightLocation.Intensity;
/*GET COLORS*/
int Width = v.Width;
int Height = v.Height;
Color[] Data = new Color[Width * Height];
ScreenImage.GetData<Color>(Data);
/*VARIABLES TO SET COLOR*/
Color[] SetColorData = new Color[Width * Height];
/*CIRCEL*/
int Radius = 15 / 2; // Define range to middle [Radius]
int Area = (int)Math.PI * (Radius * Radius);
for (int X = 0; X < Width; X++)
{
for (int Y = 0; Y < Height; Y++)
{
int Destination = X + Y * Width;
#region Light
/*GET COLOR*/
Color nColor = Data[Destination];
/*CREATE NEW COLOR*/
Vector2 MiddlePos = new Vector2(LightLocation.LightLocation.X + Radius, LightLocation.LightLocation.Y + Radius);
Vector2 CurrentLocation = new Vector2(X, Y);
float Distance;
Distance = Vector2.Distance(MiddlePos, CurrentLocation);
Distance *= 100;
Distance /= MathHelper.Clamp(Range, 0, 100);
Vector3 newColors = nColor.ToVector3();
nColor = new Color(
newColors.X,
newColors.Y,
newColors.Z,
Distance / 100);
/*SET COLOR*/
SetColorData[Destination] = nColor; // Add to array
#endregion
#region Shadow
#endregion
}
}
ScreenImage.SetData<Color>(SetColorData);
Images[curCount] = ScreenImage;
curCount++;
}
return Images[0]; // Temporarily returning the first image of the array.
}
}
As you can see, this is a slow and bad method. So I was wondering, is there a better way to get & set each pixel?
Thanks in advance, dotTutorials! =)

I think that job would be best done in a pixel shader.
You could create an Effect file that operates over one light at a time.XNA uses DX9 so you'll be limited to 128 constant registers, which I think you can use to squeeze up to three lights.
So you set your lightmap as a render target, loop through all the lights, set the constant data on your effect, render a render-target-sized quad and in your pixel shader compute your lighting equation.
In essence something like that:
// In LoadContent
RenderTarget2D lightmapRT = new RenderTarget2D(graphics.GraphicsDevice,
128,
128,
false, //No mip-mapping
SurfaceFormat.Color,
DepthFormat.Depth24);
// We now render to the lightmap in Render method
graphics.GraphicsDevice.SetRenderTarget(lightmapRT);
// Lightmap is black by default
graphics.GraphicsDevice.Clear(Color.Black);
// Use the sprite batch to draw quads with custom shader
spriteBatch.Begin(0, BlendState.Opaque, null, null, null, lightmapFx);
foreach (var light in lights)
{
// Pass the light parameters to the shader
lightmapFx.Parameters["Viewport"].SetValue(new Vector2(GraphicsDevice.Viewport.Width, GraphicsDevice.Viewport.Height));
lightmapFx.Parameters["Range"].SetValue(light.Range);
lightmapFx.Parameters["Intensity"].SetValue(light.Intensity);
lightmapFx.Parameters["LightColor"].SetValue(light.LightColor);
lightmapFx.Parameters["LightLocation"].SetValue(light.LightLocation);
// Render quad
spriteBatch.Draw(...);
}
spriteBatch.End();
And the FX file would look something like that:
float Range;
float Intensity;
float3 LightColor;
float2 LightLocation;
float2 Viewport;
struct VStoPS
{
float4 Position : POSITION0;
float2 TexCoord : TEXCOORD0;
};
VStoPS VS(in float4 color : COLOR0,
in float2 texCoord : TEXCOORD0,
in float4 position : POSITION0)
{
VStoPS vsout = (VStoPS)0;
// Half pixel offset for correct texel centering.
vsout.Position.xy -= 0.5;
// Viewport adjustment.
vsout.Position.xy = position.xy / Viewport;
vsout.Position.xy *= float2(2, -2);
vsout.Position.xy -= float2(1, -1);
// Pass texcoords as is
vsout.TexCoord = texCoord;
return vsout;
}
float4 PS(VStoPS psin)
{
// Do calculations here
// Here I just set it to white
return float4(1.0f, 1.0f, 1.0f, 1.0f);
}
technique Main
{
pass p0
{
VertexShader = compile vs_3_0 VS();
PixelShader = compile ps_3_0 PS();
}
}
Note that this non-tested code and probably full of errors. I leave it up to you to figure out what needs to go in the pixel shader.

How to this cube to draw in XNA with C#

Ok guys, this one is literally killing my mind, as I've been able to render models just fine
(in fact I had to in order to test out my camera).
However now that I'm trying to draw a cube from a vertex and index buffer, it just won't work.
(I've been able to draw triangles and such, but never from their own class).
My end goal is to be able to build regions of 64x64x8 cubes to create the game world.
(Not a minecraft clone, actually an RTS -- it'll have a "2d" feel in that the game world itself will only ever be 8 cubes deep, but I digress).
From looking over the various index & vertex tutorials all over the web, it looks to me like this should work. Here's some code.....
game.cs
protected override void Update(GameTime gameTime)
{
// Allows the game to exit
if(GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
// TODO: Add your update logic here
float timeDifference = (float)gameTime.ElapsedGameTime.TotalMilliseconds / 1000.0f;
cam.Update(timeDifference);
base.Update(gameTime);
}
protected override void Draw(GameTime gameTime)
{
GraphicsDevice.Clear(Color.CornflowerBlue);
// TODO: Add your drawing code here
cube = new CubeShape(Color.Black, new Vector3(0, 0, 0), GraphicsDevice);
RasterizerState rasterizerState = new RasterizerState();
rasterizerState.CullMode = CullMode.None;
GraphicsDevice.RasterizerState = rasterizerState;
cube.Render(cam.viewMatrix,cam.projectionMatrix);
base.Draw(gameTime);
}
}
and my cube (this one is kind of long, sorry)
class CubeShape
{
//Transform later to have static v and i buffers.
private VertexBuffer vBuffer;
public VertexBuffer VBuffer
{ get { return vBuffer; } set { vBuffer = value; } }
private IndexBuffer iBuffer;
public IndexBuffer IBuffer
{ get { return iBuffer; } set { iBuffer = value; } }
private BasicEffect bEffect;
public BasicEffect BEffect
{ get { return bEffect; } set { bEffect = value; } }
private Matrix world;
public Matrix World
{ get { return world; } set { world = value; } }
private Matrix view;
public Matrix View
{ get { return view; } set { view = value; } }
private Matrix projection;
private Matrix Projection
{ get { return projection; } set { projection = value; } }
private Color color;
public Color Color
{ get { return color; } set { color = value; } }
private Vector3 position;
public Vector3 Position
{ get { return position; } set { position = value; } }
//Need to change this eventually to use textures.
private VertexPositionColor[] vertices;
byte[] indices;
private GraphicsDevice device;
//constructors!
public CubeShape(Color inColor,Vector3 inPosition,GraphicsDevice inDevice)
{
device = inDevice;
this.color = inColor;
this.position = inPosition;
SetUpVertices();
SetUpIndices();
//world = Matrix.CreateTranslation(position);
world = Matrix.CreateTranslation(0, 0, 0);
bEffect = new BasicEffect(device);
bEffect.World = world;
bEffect.VertexColorEnabled = true;
}
//end constructors!
// >.<
public void Render(Matrix view,Matrix projection)
{
bEffect.View = view;
bEffect.Projection = projection;
device.SetVertexBuffer(vBuffer);
device.Indices = IBuffer;
foreach(EffectPass pass in bEffect.CurrentTechnique.Passes)
{
pass.Apply();
device.DrawIndexedPrimitives(PrimitiveType.TriangleList, 0, 0, 8, 0, 12);
}
}
/// <summary>
/// Sets up the vertices for a cube using 8 unique vertices.
/// Build order is front to back, left to up to right to down.
/// </summary>
private void SetUpVertices()
{
vertices = new VertexPositionColor[8];
//front left bottom corner
vertices[0] = new VertexPositionColor(new Vector3(0, 0, 0), color);
//front left upper corner
vertices[1] = new VertexPositionColor(new Vector3(0, 100, 0), color);
//front right upper corner
vertices[2] = new VertexPositionColor(new Vector3(100, 100, 0), color);
//front lower right corner
vertices[3] = new VertexPositionColor(new Vector3(100, 0, 0), color);
//back left lower corner
vertices[4] = new VertexPositionColor(new Vector3(0, 0, -100), color);
//back left upper corner
vertices[5] = new VertexPositionColor(new Vector3(0, 100, -100), color);
//back right upper corner
vertices[6] = new VertexPositionColor(new Vector3(100, 100, -100), color);
//back right lower corner
vertices[7] = new VertexPositionColor(new Vector3(100, 0, -100), color);
vBuffer = new VertexBuffer(device, typeof(VertexPositionColor), 8, BufferUsage.WriteOnly);
vBuffer.SetData<VertexPositionColor>(vertices);
}
/// <summary>
/// Sets up the indices for a cube. Has 36 positions that match up
/// to the element numbers of the vertices created earlier.
/// Valid range is 0-7 for each value.
/// </summary>
private void SetUpIndices()
{
indices = new byte[36];
//Front face
//bottom right triangle
indices[0] = 0;
indices[1] = 3;
indices[2] = 2;
//top left triangle
indices[3] = 2;
indices[4] = 1;
indices[5] = 0;
//back face
//bottom right triangle
indices[6] = 4;
indices[7] = 7;
indices[8] = 6;
//top left triangle
indices[9] = 6;
indices[10] = 5;
indices[11] = 4;
//Top face
//bottom right triangle
indices[12] = 1;
indices[13] = 2;
indices[14] = 6;
//top left triangle
indices[15] = 6;
indices[16] = 5;
indices[17] = 1;
//bottom face
//bottom right triangle
indices[18] = 4;
indices[19] = 7;
indices[20] = 3;
//top left triangle
indices[21] = 3;
indices[22] = 0;
indices[23] = 4;
//left face
//bottom right triangle
indices[24] = 4;
indices[25] = 0;
indices[26] = 1;
//top left triangle
indices[27] = 1;
indices[28] = 5;
indices[29] = 4;
//right face
//bottom right triangle
indices[30] = 3;
indices[31] = 7;
indices[32] = 6;
//top left triangle
indices[33] = 6;
indices[34] = 2;
indices[35] = 3;
iBuffer = new IndexBuffer(device, typeof(short), 36, BufferUsage.WriteOnly);
iBuffer.SetData(indices);
}
}
I really have no clue why this isn't working. Probably because I've been having a staredown with the code for the last 4 hours >.<
Oh, the camera starts at 0,0,50 and is facing 0,0,0. It also allows me to move around with the mouse and keyboard (like any rts cam should) with rotation (middle mouse button held down). I've searched all around just to make sure my cube wasn't somewhere outside of my view range,but all I see is blue >.<
I'd appreciate any help here.
p.s. as a secondary question, any hints on how to share buffers between cubes?
I read that since the geometry of a cube never changes, that it's more efficient to share buffers but I'm not sure how to go about this...create one decently big buffer and fill it with cubes from some kind of list class that holds all the cubes that need to be rendered maybe? not even sure where to start looking. Again, thanks much for any input/advice.

It looks like you have some typing issues. I got it to work by changing the following code:
//byte[] indices;
short[] indices;
//indices = new byte[36];
indices = new short[36];
//iBuffer = new IndexBuffer(device, typeof(short), 36, BufferUsage.WriteOnly);
iBuffer = new IndexBuffer(device, IndexElementSize.SixteenBits, sizeof(short) * indices.Length, BufferUsage.WriteOnly);
If it still does not work, yell at me and I will check to make sure that I did not miss anything. Keep in mind, I had to use one of my own camera classes since you did not include yours.
I am not sure how to answer your second question. You might want to ask it as a separate question.