2d

I have started making something on pygame but I have encountered an issue when moving left or right. if I quickly change from pressing the right arrow key to pressing the left one and also let go of the right one the block just stops moving. this is my code bg = "sky.jpg" ms = "ms.png" import pygame, sys from pygame.locals import * x,y = 0,0 movex,movey=0,0 pygame.init() screen=pygame.display.set_mode((664,385),0,32) background=pygame.image.load(bg).convert() mouse_c=pygame.image.load(ms).convert_alpha() m = 0 pygame.event.pump() while 1: for event in pygame.event.get(): if event.type == QUIT:

I have a collection of 2D coordinate sets (on the scale of a 100K-500K points in each set) and I am looking for the most efficient way to measure the similarity of 1 set to the other. I know of the usuals: Cosine, Jaccard/Tanimoto, etc. However I am hoping for some suggestions on any fast/efficient ones to measure similarity, especially ones that can cluster by similarity. Edit 1: The image shows what I need to do. I need to cluster all the reds, blues and greens by their shape/orientatoin, etc. alt text http://img402.imageshack.us/img402/8121/curves.png It seems that the first step of any

I'm drawing a ground texture in a sidescrolling platformer like this: spriteBatch.Begin(SpriteSortMode.Deferred, null, null, null, null, null, _camera.GetViewMatrix(Parallax)); foreach (Sprite sprite in Sprites) sprite.Draw(spriteBatch); spriteBatch.End(); In Sprite.Draw() public void Draw(SpriteBatch spriteBatch) { if (Texture != null) spriteBatch.Draw(Texture, Position, new Rectangle(0, 0, Texture.Width, Texture.Height), Color.White, Rotation, Origin, Scale, SpriteEffects.None, ZIndex); } How can I get the texture to repeat in the X Direction infinitely? Any resources explaining how to do

How can I pull the first column from my 2D array? I am initialising my array in a method like this //Initialise the array with the values from the file public static float[][] data(float[][] data, Scanner scan){ int count = 0; for (int i=0;i<data.length;i++){ for (int j=0;j<data[0].length;j++){ count++; if(count<data.length*data[0].length){ for(int k=0;k<2; k++){ data[i][j] = (float) IOUtil.skipToDouble(scan); System.out.print(data[i][j] + " "); } System.out.println(); } } } return data; } This is the contents of my test file. (Please bare in mind the file could be any length) 13.97 2.2 12.05

Assume you are given the equation of a line (in 2d), and the equations of lines that form a convex polygon (the polygon could be unbounded). How do I determine if the line intersects the polygon? Furthermore, are there computational geometry libraries where such tasks are pre-defined? I ask because I'm interested not just in the 2D version but n-dimensional geometry. For the 2D case, I think the problem simplifies a bit. The line partitions the space into two regions. If the polygon is present in only one of those regions, then the line does not intersect it. If the polygon is present in both