point

问题 I just recognized my math is a bit rusty.. I wanna check if Point C is between Point A and Point B . C can be on the line segment of A and B, or not. There can be three cases and I have to identify all of them: C is between A and B C / \ A---B C is in front of A and B C \ \ A--B C is in the back of A and B C / / A--B The "sketch" in the last two points should be a triangle. I used the dotproduct to check if C is between A and B. if (VectorOf(AB) * VectorOf(BC)) >= 0) To check if C is in the

问题 By now points can be drawn with the following code: // SETUP FOR VERTICES GLfloat points[graph->vertexCount * 6]; for (int i = 0 ; i < graph->vertexCount; i++) { points[i*6] = (graph->vertices[i].x / (backingWidth/2) ) - 1; points[i*6+1] = -(graph->vertices[i].y / (backingHeight/2) ) + 1; points[i*6+2] = 1.0; points[i*6+3] = 0.0; points[i*6+4] = 0.0; points[i*6+5] = 1.0; } glEnable(GL_POINT_SMOOTH); glPointSize(DOT_SIZE*scale); glVertexPointer(2, GL_FLOAT, 24, points); glColorPointer(4, GL

问题 I'm trying to write a Python function (without the use of modules) that will iterate through a list of coordinates and find the euclidean distance between two subsequent points (for example, the distance between points a and b, b and c, c and d etc.). After a few hours of searching I came across this post which I thought solved my problem, so I wrote this: myList = [[2, 3], [3,4], [4,5], [5,6], [6,7]] def distance(pointOne,pointTwo): eucDist = ((pointOne[0] - pointTwo[0])**2 + (pointOne[1] -

问题 For a project we're making a topdown-view game. Characters can turn and walk in all directions, and are represented with a point and an angle. The angle is calculated as the angle between the current facing direction and to the top of the program, and can be 0-359. I have the following code for the movement: public void moveForward() { position.x = position.x + (int) (Math.sin(Math.toRadians(angle)) * speed); position.y = position.y + (int) (Math.cos(Math.toRadians(angle)) * speed); } public

问题 I'm trying to find my relative coordinate for a usercontrol inside my mainwindow. I tried using the "Control.PointToScreen()" method but with no luck. Everytime I do this i get an exception that says: System.InvalidOperationException: This Visual is not connected to a PresentationSource I think this has something to do with me calling pointToScreen before the visuals have rendered properly, since i'm already calling the method in my Mains Constructor. Anyways, I would like to hear if anyone

问题 I have QPainterPath. I need to find y coordinate of QPainterPath by x. I found intersected() method in QPainterPath. So, I created new QPainterPath, which is line from left to right edge of my path's bounding rect with x coordinate, to find point as result of intersection. intersects() method returns true. But intersected() returns empty path. Everything works If I use rect with height = 1 instead of line. Maybe you have a better idea how to find intersection of QPainterPath with line? 回答1:

问题 Is there any way to actually see the source code of standard java classes by the way? I'm making a hash table of points ( HashSet<Point> ) and I want to make sure that it will hash well, but I can't see what Point's hashCode() method actually looks like, so I don't know how good it really is. Can anyone help me? Should I override it? And if so, is there an easy way to do this without creating a whole new java file/class? 回答1: If you're searching for the hashCode() of java.awt.Point , it is

问题 I am using the XC32 compiler from Microchip, which is based on the standard C compiler. I am reading a 32bit value from a device on a RS485 network and storing this in a unsigned long that I have typedef'ed as DWORD. i.e. typedef DWORD unsigned long; As it stands, when I typecast this value to a float, the value I get is basically the floating point version of it's integer representation and not the proper IEEE-754 interpreted float. i.e. DWORD dword_value = readValueOnRS485(); float temp =

问题 how to draw full circle or point with canvas? I using canvas and path + paint classes my code: @Override public boolean onTouchEvent(MotionEvent event) { float eventX = event.getX(); float eventY = event.getY(); System.out.println(event.getAction()); switch (event.getAction()) { case MotionEvent.ACTION_DOWN: path.moveTo(eventX, eventY); return true; case MotionEvent.ACTION_MOVE: path.lineTo(eventX, eventY); break; case MotionEvent.ACTION_UP: path.addCircle(eventX, eventY, .1F, Path.Direction

问题 How do we check whether (point) is within matching "quotes" Example 1: " (point) ", but not within Example 2: "quote here" (point) "quote there", in Emacs Lisp? 回答1: What you are looking for is syntax-ppss (defined in syntax.el ). It returns 10 values, and the 4th tells you whether the point is inside a string. 回答2: (eq (nth 1 (text-properties-at (point))) font-lock-string-face) This checks whether the font of the text at point is recognized as a string (i.e. has the text property face font