projection

问题 I have a Customer entity from which I only want to select a few fields and their associated CustomerAddresses. I've defined a Spring Data JPA projection interface as follows: public interface CustomerWithAddresses { Integer getId(); String getFirstName(); String getLastName(); String getBrandCode(); String getCustomerNumber(); Set<CustomerAddress> getCustomerAddresses(); } But from my Repository method: CustomerWithAddresses findCustomerWithAddressesById(@Param("id") Integer id); I keep

问题 I did a lot of searching but didn't find any solutions to this problem. I have a viewport where the center (where we are looking from) is always at (0,0,0). We are always looking in the direction of (0,0,1). After doing all my math, it simplified to: Projected X = 3D X Coordinate / 3D Z Coordinate Projected Y = 3D Y Coordinate / 3D Z Coordinate And it works perfectly. Every point is correctly projected onto the plane at z=1. But there is an issue with negatives depths. I could just not render

问题 I'm trying to compute 2d projections of a 3d mesh from different views using matlab. The solution I m using now, is to plot the 3d mesh, rotate it, and make a screenshot. I would like to know if there is any matlab internal functions or any other solution that allow me, given a set of vertices and triangles, to compute the projections without having to plot the 3D mesh Thanks 回答1: You can use the view command to rotate the axes and change the viewpoint. The azimuth and elevation are given in

问题 How can I do a lambert-azimuthal equal area projection with the mapproj package? http://cran.r-project.org/web/packages/mapproj/mapproj.pdf There is azequalarea() equal-area and lambert(lat0,lat1) conformal, true scale on lat0 and lat1 What one is closests to lambert-azimuthal equal area projection? 回答1: In package mapproj , and the function mapproject() , it seems that the Lambert-azimuthal equal area projection would be azequalarea() since lambert(lat0,lat1) is the Lambert Conformal Conic

问题 I calibrated my mono camera using opencv. Now I know the camera intrinsic matrix and distortion coefs [K1, K2, P1 ,P2,K3 ,K4, K5, K6] of my camera. Assuming that camera is place in [x, y, z] with [Roll, Pitch, Yaw] rotations. how can I get each pixel in world coordinate when the camera is looking on the floor [z=0]. 回答1: You say that you calibrated your camera which gives you: Intrinsic parameters Extrinsic parameters (rotation, translation) Distortion coefficients First, to compensate for

问题 I'm trying to build my own Rasteriser/Graphics pipeline (mimicking OpenGL) from scratch and I'm having problems with implementing a working perspective projection matrix. This is my current attempt: template<typename T> Matrix<T,4,4> Perspective(T fov,T aspect, T near, T far) { T mat00 = 1 / (aspect*tan(0.5f*fov)); T mat11 = 1 / tan(0.5f*fov); T mat22 = (-near-far)/(near-far); T mat32 = (2*near*far)/(near-far); T data[] = { mat00, 0, 0, 0, 0 , mat11, 0, 0, 0 , 0, mat22,mat32, 0 , 0, 1, 0 };

问题 I'm looking at the custom projection example in the matplotlib gallery -- I'm trying to modify it to plot only the southern hemisphere. I have adjusted the necessary [-pi/2,pi/2] limits to [-pi/2,0]. Now I've been looking at: def _gen_axes_patch(self): """ Override this method to define the shape that is used for the background of the plot. It should be a subclass of Patch. In this case, it is a Circle (that may be warped by the axes transform into an ellipse). Any data and gridlines will be

问题 I am lazy loading the collections, and also because there are so many fields within the person table, I am writing a projection function to retrieve only certain properties. It works with properties, just not collections of other entities. I would be fine if they were loaded in as proxies and i could get them later, but right now it just loads in null. public IList<Person> ListTop40() { var list = _session.CreateCriteria(typeof(Person)) .SetProjection(Projections.ProjectionList() .Add

问题 Given a picture taken by a simple digital that contains an image of a rectangle of known dimensions. How can I - to some degree of accuracy - determine the parameters of this camera? I am mostly interested in Pan-, Tilt- and Swing angles. Optionally distance to the rectangle would be nice. I acknowledge the fact that the focal length and resolution of the camera should be known, but it can be assumed that they are available (for example through exif metadata). Are there any simple algorithms

问题 I am using this legacy code: http://fossies.org/dox/opencv-2.4.8/trifocal_8cpp_source.html for estimating 3D points from the given corresponding 2D points from 3 different views. The problem I faced is same as stated here: http://opencv-users.1802565.n2.nabble.com/trifocal-tensor-icvComputeProjectMatrices6Points-icvComputeProjectMatricesNPoints-td2423108.html I could compute Projection matrices successfully using icvComputeProjectMatrices6Points . I used 6 set of corresponding points from 3