Search Results

Search found 812 results on 33 pages for 'computational geometry'.

Page 6/33 | < Previous Page | 2 3 4 5 6 7 8 9 10 11 12 13  | Next Page >

  • Find the new coordinates using a starting point, a distance, and an angle

    - by dqhendricks
    Okay, say I have a point coordinate. var coordinate = { x: 10, y: 20 }; Now I also have a distance and an angle. var distance = 20; var angle = 72; The problem I am trying to solve is, if I want to travel 20 points in the direction of angle from the starting coordinate, how can I find what my new coordinates will be? I know the answer involves things like sin/cosin, because I used to know how to do this, but I have since forgotten the formula. Can anyone help?

    Read the article

  • How to calculate direction from initial point and another point?

    - by Dvole
    I'm making a simple game where I shoot things from a certain point on screen (A). I tap the screen and shoot the projectile from initial point(A) to the tap point(B). But I want the projectile to move along the same path instead and fly out of bounds of the screen. How do I calculate a point that is on the same line that these two points, but further away? This is a simple math, but I can't figure it out.

    Read the article

  • Intersection of player and mesh

    - by Will
    I have a 3D scene, and a player that can move about in it. In a time-step the player can move from point A to point B. The player should follow the terrain height but slow going up cliffs and then fall back, or stop when jumping and hitting a wall and so on. In my first prototype I determine the Y at the player's centre's X,Z by intersecting a ray with every triangle in the scene. I am not checking their path, but rather just sampling their end-point for each tick. Despite this being Javascript, it works acceptably performance-wise. However, because I am modeling the player as a single point, the player can position themselves so that they are half-in a cliff face and so on. I need to model them as as a solid e.g. some cluster of spheres or a even their fuller mesh. I am also concerned that if they were moving faster they might miss the test altogether. How should I solve this?

    Read the article

  • moving in the wrong direction

    - by Will
    Solution: To move a unit forward: forward = Quaternion(0,0,0,1) rotation.normalize() # ocassionally ... pos += ((rotation * forward) * rotation.conjugated()).xyz().normalized() * speed I think the trouble stemmed from how the Euclid math library was doing Quaternion*Vector3 multiplication, although I can't see it. I have a vec3 position, a quaternion for rotation and a speed. I compute the player position like this: rot *= Quaternion().rotate_euler(0.,roll_speed,pitch_speed) rot.normalize() pos += rot.conjugated() * Vector3(0.,0.,-speed) However, printing the pos to console, I can see that I only ever seem to travel on the x-axis. When I draw the scene using the rot quaternion to rotate my camera, it shows a proper orientation. What am I doing wrong? Here's an example: You start off with rotation being an identity quaternion: w=1,x=0,y=0,z=0 You move forward; the code correctly decrements the Z You then pitch right over to face the other way; if you spin only 175deg it'll go in right direction; you have to spin past 180deg. It doesn't matter which direction you spin in, up or down, though Your quaternion can then be something like: w=0.1,x=0.1,y=0,z=0 And moving forward, you actually move backward?! (I am using the euclid Python module, but its the same as every other conjulate) The code can be tried online at http://williame.github.com/ludum_dare_24_evolution/ The only key that adjusts the speed is W and S. The arrow keys only adjust the pitch/roll. At first you can fly ok, but after a bit of weaving around you end up getting sucked towards one of the sides. The code is https://github.com/williame/ludum_dare_24_evolution/blob/cbacf61a7159d2c83a2187af5f2015b2dde28687/tiny1web.py#L102

    Read the article

  • Rotate an object given only by its points?

    - by d33tah
    I was recently writing a simple 3D maze FPP game. Once I was done fiddling with planes in OpenGL, I wanted to add support for importing Blender objects. The approach I used was triangulization of the object, then using Three.js to export the points to plaintext and then parsing the result JSON in my app. The example file can be seen here: https://github.com/d33tah/tinyfpp/blob/master/Data/Models/cross.txt The numbers represent x,y,z,u,v of a single vertex, which combined in three make a triangle. Then I rendered such an object triangle-by-triangle and played with it. I could move it back and forth and sideways, but I still have no idea how to rotate it by some axis. Let's say I'd like to rotate all the points by five degrees to the left, how would a code doing it look like?

    Read the article

  • Value object or not for 3d points ?

    - by Stefano Borini
    I need to develop a geometry library in python, describing points, lines and planes in 3d space, and various geometry operations. Related to my previous question. The main issue in the design is if these entities should have identity or not. I was wondering if there's a similar library out there (developed in another language) to take inspiration from, what is the chosen design, and in particular the reason for one choice vs. the other.

    Read the article

  • Creating SVG map from geometry stored in MySQL

    - by Barnabe
    I have a group of geometries stored in MySQl (as polygon and as well-known text) representing counties. I can build a table of geometries and color codes after querying some county data (say GDP per capita). What is the best way to export this as an SVG map? I cannot find any reference to SVG conversion in the MySQL documentation.

    Read the article

  • Code to extrude 2d geometry to 3d

    - by Bgnt44
    Hi, is there any simple way to extrude a 2d geomtry (vectors ) to a 3d shape assuming extruding parameter are lenght (double) and angle (degree) so it should render like a cone ( all z lines going to one point )

    Read the article

  • Create Linework/Geometry Using Text Style in AutoCAD

    - by Kratz
    I'm working in AutoCAD using the ObjectARX .Net API. Is there a way to either create text using lines/curves/polylines, or explode an existing text object into lines/ect? Prefereable I would like to be able to generate linework based on an exsiting AutoCAD text style. Edit: I was able to find the source for the TxtExp command here . However its in AutoCADs own Lisp language, and I can't make heads or tails of it.

    Read the article

  • What library should I use for 2D Geometry? [closed]

    - by Luka
    I've been working on a 2D game in java, but found that java just didn't cut it for me and had forced me to a lot of bad design choices, so I've decided to port all my work to c++. The main reason I've decided change to c++ is that i had reached a point where i had 3 geometry libraries (the native, one from the game engine and one to handle "complex" polygons), none of witch worked very well together and i couldn't keep track of them. I'm new to c++, but i know all the basics. My question is, what would be a good geometry library to use, ideally it should be able to handle integer and decimal data types, have point, line, and polygon classes witch are able to check for intersection and contains. Thanks in advance, Luka

    Read the article

  • Intersections of 3D polygons in python

    - by Andrew Walker
    Are there any open source tools or libraries (ideally in python) that are available for performing lots of intersections with 3D geometry read from an ESRI shapefile? Most of the tests will be simple line segments vs polygons. I've looked into OGR 1.7.1 / GEOS 3.2.0, and whilst it loads the data correctly, the resulting intersections aren't correct, and most of the other tools available seem to build on this work. Whilst CGAL would have been an alternative, it's license isn't suitable. The Boost generic geometry library looks fantastic, but the api is huge, and doesn't seem to support wkt or wkb readers out of the box.

    Read the article

  • Collision detection, alternatives to "push out"

    - by LaZe
    I'm moving a character (ellipsoid) around in my physics engine. The movement must be constrained by the static geometry, but should slide on the edges, so it won't be stuck. My current approach is to move it a little and then push it back out of the geometry. It seems to work, but I think it's mostly because of luck. I fear there must be some corner cases where this method will go haywire. For example a sharp corner where two walls keeps pushing the character into each other. How would a "state of the art" game engine solve this?

    Read the article

  • Mixing a4 and a3 in one Latex file

    - by jorgusch
    Hello, I am finishing my thesis and have a large appendix. Some tables only look good, if first done on a3 and then (paper)printed on a4. Anyhow, working all the files seperalty is fine, but I struggle to compile all in one. I use the geometry package and start the document with: \usepackage[a4paper,left=30mm,right=20mm,top=20mm, bottom=20mm]{geometry} For the appendix, I want to include the table and use \newgeometry{a3paper,left=25mm,right=15mm, top=15mm, bottom=15mm} However, the command is completely ignored and I can read "a3paper,left=25mm,right=15mm, top=15mm, bottom=15mm" above the table. What did I miss? Is it even possible? If not, how do I get the numbers right, if I have to include it as a pdf (which works)? Thanks!

    Read the article

  • What causes player box/world geometry glitches in old games?

    - by Alexander
    I'm looking to understand and find the terminology for what causes - or allows - players to interfere with geometry in old games. Famously, ID's Quake3 gave birth to a whole community of people breaking the physics by jumping, sliding, getting stuck and launching themselves off points in geometry. Some months ago (though I'd be darned if I can find it again!) I saw a conference held by Bungie's Vic DeLeon and a colleague in which Vic briefly discussed the issues he ran into while attempting to wrap 'collision' objects (please correct my terminology) around environment objects so that players could appear as though they were walking on organic surfaces, while not clipping through them or appear to be walking on air at certain points, due to complexities in the modeling. My aim is to compose a case study essay for University in which I can tackle this issue in games, drawing on early exploits and how techniques have changed to address such exploits and to aid in the gameplay itself. I have 3 current day example of where exploits still exist, however specifically targeting ID Software clearly shows they've massively improved their techniques between Q3 and Q4. So in summary, with your help please, I'd like to gain a slightly better understanding of this issue as a whole (its terminology mainly) so I can use terms and ask the right questions within the right contexts. In practical application, I know what it is, I know how to do it, but I don't have the benefit of level design knowledge yet and its technical widgety knick-knack terms =) Many thanks in advance AJ

    Read the article

  • how do I add a texture to a triangle in three.js?

    - by Kae Verens
    I've created a scene which has many cubes, spheres, etc, in it, and have been able to apply textures to those primitives, but when I want to add a texture to a simple triangle, I'm totally lost. Here's the closest I've come to getting it right: var texture=THREE.ImageUtils.loadTexture('/f/3d-images/texture-steel.jpg'); var materialDecalRoof=new THREE.MeshBasicMaterial( { 'map': texture, 'wireframe': false, 'overdraw': true } ); var geometry = new THREE.Geometry(); geometry.vertices.push(new THREE.Vector3(tentX/2+1, tentY, tentZ/2+1)); geometry.vertices.push(new THREE.Vector3(0, tentT, 0)); geometry.vertices.push(new THREE.Vector3(0, tentT, 0)); geometry.vertices.push(new THREE.Vector3(-tentX/2-1, tentY, tentZ/2+1)); geometry.faces.push(new THREE.Face4(0, 1, 2, 3)); geometry.faceVertexUvs[0].push([ new THREE.UV(0, 0), new THREE.UV(0, 0), new THREE.UV(0, 0), new THREE.UV(0, 0) ]); geometry.computeFaceNormals(); geometry.computeCentroids(); geometry.computeVertexNormals(); var mesh= new THREE.Mesh( geometry, materialDecalRoof); scene.add(mesh); This does not work. All i get is a flickering triangle (when the scene is moved) where an image should be. To test this, go to https://www.poptents.eu/3dFrame.php, upload an image in the Roof section, and drag the view to see the roof flicker. Does anyone know what I'm doing wrong here?

    Read the article

  • Draw Lines Over a Circle

    - by VOX
    There's a line A-B and C at the center between A and B. It forms a circle as in the figure. If we assume A-B line as a diameter of the circle and then C is it's center. My problem is I have no idea how to draw another three lines (in blue) each 45 degree away from AC or AB. No, this is not a homework, it's part of my complex geometry in a rendering. http://www.freeimagehosting.net/image.php?befcd84d8c.png

    Read the article

  • Qt- how to set QWidget width

    - by Narek
    How to set QWidget width? I know setGeometry(QRect& rect) function to do that, but in that case I should use geometry() function to get former parameters of my QWidget, then I should increment the width and use setGeometry(..). Is there any ditect way to say QWidget aa; aa.setWidth(165); //something like this?

    Read the article

  • Faster way to compare two sets of points in N-dimensional space?

    - by Amit
    List1 contains a high number (~7^10) of N-dimensional points (N <=10), List2 contains the same or fewer number of N-dimensional points (N <=10). My task is this: I want to check which point in List2 is closest (euclidean distance) to a point in List1 for every point in List1 and subsequently perform some operation on it. I have been doing it the simple- the nested loop way when I didn't have more than 50 points in List1, but with 7^10 points, this obviously takes up a lot of time. What is the fastest way to do this? Any concepts from Computational Geometry might help?

    Read the article

  • What is an Efficient algorithm to find Area of Overlapping Rectangles

    - by namenlos
    My situation Input: a set of rectangles each rect is comprised of 4 doubles like this: (x0,y0,x1,y1) they are not "rotated" at any angle, all they are "normal" rectangles that go "up/down" and "left/right" with respect to the screen they are randomly placed - they may be touching at the edges, overlapping , or not have any contact I will have several hundred rectangles this is implemented in C# I need to find The area that is formed by their overlap - all the area in the canvas that more than one rectangle "covers" (for example with two rectangles, it would be the intersection) I don't need the geometry of the overlap - just the area (example: 4 sq inches) Overlaps shouldn't be counted multiple times - so for example imagine 3 rects that have the same size and position - they are right on top of each other - this area should be counted once (not three times) Example The image below contains thre rectangles: A,B,C A and B overlap (as indicated by dashes) B and C overlap (as indicated by dashes) What I am looking for is the area where the dashes are shown - AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA--------------BBB AAAAAAAAAAAAAAAA--------------BBB AAAAAAAAAAAAAAAA--------------BBB AAAAAAAAAAAAAAAA--------------BBB BBBBBBBBBBBBBBBBB BBBBBBBBBBBBBBBBB BBBBBBBBBBBBBBBBB BBBBBB-----------CCCCCCCC BBBBBB-----------CCCCCCCC BBBBBB-----------CCCCCCCC CCCCCCCCCCCCCCCCCCC CCCCCCCCCCCCCCCCCCC CCCCCCCCCCCCCCCCCCC CCCCCCCCCCCCCCCCCCC

    Read the article

  • Math problem: Determine the corner radius of an inner border based on outer corner radius/thickness

    - by chaiguy
    Here's a math/geometry problem for the math whizzes (not my strongest subject). This is for WPF, but should be general enough to solve regardless: I have two embedded Border elements, with the outer one having a certain corner radius, R and border thickness, T. Given these two values, what should the corner radius of the inner Border, R' be set to such that the two corner edges meet with no overlap or holes? So far I've just been eyeballing it, but if someone can give me a proper formula that would be great. Respect points if you can!! ;)

    Read the article

  • How to calculate both positive and negative angle between two lines?

    - by Jaanus
    There is a very handy set of 2d geometry utilities here. The angleBetweenLines has a problem, though. The result is always positive. I need to detect both positive and negative angles, so if one line is 15 degrees "above" or "below" the other line, the shape obviously looks different. The configuration I have is that one line remains stationary, while the other line rotates, and I need to understand what direction it is rotating in, by comparing it with the stationary line. EDIT: in response to swestrup's comment below, the situation is actually that I have a single line, and I record its starting position. The line then rotates from its starting position, and I need to calculate the angle from its starting position to current position. E.g if it has rotated clockwise, it is positive rotation; if counterclockwise, then negative. (Or vice versa.) How to improve the algorithm so it returns the angle as both positive or negative depending on how the lines are positioned?

    Read the article

  • Math for a geodesic sphere

    - by Marcelo Cantos
    I'm trying to create a very specific geodesic tessellation, but I can't find anything online about it. It is normal to subdivide the triangles of an icosahedron into triangle patches and project them onto the sphere. However, I noticed an animated GIF on the Wikipedia entry for Geodesic Domes that appears not to follow this scheme. Geodesic spheres generally comprise a mixture of mostly hexagonal triangle patches, with pentagonal patches forming at the vertices of the original icosahedron; in most cases, these pentagons are linked together; that is, following a straight edge from the center of one pentagon leads to the center of another pentagon. In the Wikipedia animation, however, the edge from the center of one pentagon doesn't appear to intersect the center of an adjacent pentagons; instead it intersects the side of the other pentagon. Hopefully the drawing below makes this clear: Where can I go to learn about the math behind this particular geometry? Ideally, I'd like to know of an algorithm for generating such tessellations.

    Read the article

< Previous Page | 2 3 4 5 6 7 8 9 10 11 12 13  | Next Page >