graphics

问题 I'm currently working with JFrame and I'm trying to draw a rectangle but I don't know how to execute the code paint(Graphics g) , how do I get the Graphics object? package com.raggaer.frame; import java.awt.Dimension; import java.awt.Graphics; import javax.swing.JFrame; public class Frame { private JFrame frame; public Frame() { this.frame = new JFrame("Java Snake"); this.frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.frame.setSize(new Dimension(500, 500)); // DRAW?? this.frame

问题 I have a 4x4 projection matrix (SCNMatrix4) s = (m11 = 1.83226573, m12 = 0, m13 = 0, m14 = 0, m21 = 0, m22 = 2.44078445, m23 = 0, m24 = 0, m31 = -0.00576340035, m32 = -0.0016724075, m33 = -1.00019991, m34 = -1, m41 = 0, m42 = 0, m43 = -0.20002, m44 = 0) I would like to get the focal point and the focal length out of this matrix. 回答1: From slides 4 and 5 on this GDC presentation: The focal length is merely the first element in the matrix ( m11 ). The focal point , however, cannot be extracted

问题 The grid.pattern function supplied by gridExtra will fill a polygon with diagonal lines. I want to increase the density of lines, i.e., the number of diagonal lines that appears in any given space. Is there an argument that I can pass to grid.pattern that controls the density of lines? Here's a minimal example: library(gridExtra) grid.pattern(pattern = 1) That code draws a rectangle covered by diagonal lines. How can I change the code so that the rectangle includes (say) twice as many lines?

问题 I have a circular shape object, which I want to rotate like a fan along it's own axis. I can change the rotation in any direction i.e. dx, dy, dz using my transformation matrix. The following it's the code: Matrix4f matrix = new Matrix4f(); matrix.setIdentity(); Matrix4f.translate(translation, matrix, matrix); Matrix4f.rotate((float) Math.toRadians(rx), new Vector3f(1,0,0), matrix, matrix); Matrix4f.rotate((float) Math.toRadians(ry), new Vector3f(0,1,0), matrix, matrix); Matrix4f.rotate(

问题 I am dealing with a splash screen logo and I've noticed that on different OS versions this image gets distorted, but it happens to work when dealing with Windows 8.1, but not on Windows 7 or Vista. I've been using Adobe Fireworks in conjunction with Illustrator to generate it, and I must have tried a ton of different settings but I can't get the same experience across all operating systems. I load it into my WiX project as follows: <Binary Id="SplashBinary" SourceFile="Splash.jpg"/> And I use

问题 I have written an R function, that connect to database, fetch some records, obtain association rule of the object via arules library and plot the rules using arulesViz . I save the R function in an script file, named associationRule.R. plotAssociationRule = function(){ library(arules) library(RJDBC) jdbcDriver <- JDBC(driverClass="oracle.jdbc.OracleDriver", classPath="lib/ojdbc6-11.2.0.2.0.jar") jdbcConnection <- dbConnect(jdbcDriver, "jdbc:oracle:thin:@//172.16.1.133:1521/oradb", "hr_midhco"

问题 I made a record called automaton containing the 5 fields required to represent an automaton I'm supposed to use graphics to represent every state and transition from the transitions list without using for or while loops only recursive functions transitions :(int*char*int) list; 回答1: It might be easiest to use graphviz to do the actual drawing. It automatically draws a graph from a list of nodes and edges, which is exactly what your input is. The function fmt_transition generates one edge, the

问题 I want to add in a feature so that when the mouse goes over a button then it will add a drop shadow. Currently I'm just trying to get the mechanics to work. I have my game loop calling a update method which I know works but here it is anyway public void updateManager(double delta){ mhandler.updateCoordinates(); if(mhandler.getX() >= 144 && mhandler.getX() <= 444 && mhandler.getY() >= 784 && mhandler.getY() <= 980){ oversp = true; }else{ oversp = false; } } mhandler is what I named my

问题 I am writing the code of Game bean machine (Galton box) using animated graphics. I am using swing.Timer to make the red ball move, by letting the Timer object take an ActionListener. Here is the output: The red ball here is moving randomly : http://imgur.com/J9Xq0t5&HIv1udp And here it reaches the bottom: http://imgur.com/J9Xq0t5&HIv1udp#1 The problem is that I want to make several balls moving not only 1 but I actually cannot, I tried to put the Timer object in a loop but it only speeded up

问题 I am using two panels for drawing ruler along the sides (top and left) of a picture box. It works, but now my requirement is to flip the direction of the ruler so that the line starts from the picture box and the text (numbers) are the top. How can I do this? My code is as follows: private void panel2_Paint(object sender, PaintEventArgs e)//left Panel { Graphics g = e.Graphics; g.PageUnit = GraphicsUnit.Millimeter; int step = 1; int length = panelleft.Height / 3; int small = 5; int big = 10;