projection

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 polygons with negative depth points, but what if the triangle has other vertices that reach into the

My NetCDF file has 4 dimensions (longitude, latitude, time, level pressure) and several variables. I want to replace the longitude data which is [340 342 344 ... 360 0 2 4 ... 18 20] by [-20 -18 -16 ... -2 0 2 4 ... 18 20]. In fact the longitude is counted from 0° to 360° but I need to have it from -180° to 180°. I have found some ideas on Internet but I don't know how to apply them. Here an explanation: "Some netcdf files contain strictly positive values [0,360] which are not compatible with the way gdal/QGis treat longitude values - they do not wrap around the dateline. This also causes

I want to parse an SVG style attribute, which is just a delimited string, e.g. "fill:#e2b126;stroke:#010101;stroke-width:0.3177;stroke-miterlimit:10" into a Dictionary<string,string> so that I can perform some processing on it. Here's what I have, which does the job, but I'd like to make it neater using a linq projection, just can't seem to get the syntax. I tried using .Select().ToDictionary etc, but no joy. Thanks: string attributes = "fill:#e2b126;stroke:#010101;stroke-width:0.3177;stroke-miterlimit:10"; var pairs = attributes.Split(';').ToList(); var dic = new Dictionary<string, string>();

Here is my code to project Velodyne points into the images: cam = 2; frame = 20; % compute projection matrix velodyne->image plane R_cam_to_rect = eye(4); [P, Tr_velo_to_cam, R] = readCalibration('D:/Shared/training/calib/',frame,cam) R_cam_to_rect(1:3,1:3) = R; P_velo_to_img = P*R_cam_to_rect*Tr_velo_to_cam; % load and display image img = imread(sprintf('D:/Shared/training/image_2/%06d.png',frame)); fig = figure('Position',[20 100 size(img,2) size(img,1)]); axes('Position',[0 0 1 1]); imshow(img); hold on; % load velodyne points fid = fopen(sprintf('D:/Shared/training/velodyne/%06d.bin',frame

Let's look at m points in n-d space- (A solution for 4 points in 3-d space is here: minimize distance from sets of points ) a= (x1, y1, z1, ..) b= (x2, y2 ,z2, ..) c= (x3, y3, z3, ..) . . p= (x , y , z, ..) Find point q = c1* a + c2* b + c3* c + .. where c1 + c2 + c3 + .. = 1 and c1, c2, c3, .. >= 0 s.t. euclidean distance pq is minimized. What algorithms can be used ? Idea or pseudocode is enough. (Optimizing performance is a big issue here. Monte Carlo method with all vertices and changing coefficients would also give a solution.) We can assume p = 0 by subtracting p from all the other

I'm still implementing a perspective projection for my augmented reality application. I've already asked some questions about the viewport-calculation and other camera stuff, which is explained from Aldream in this thread However, I don't get any useful value at the moment and I think this depends on my calculation of the cartesian coordinate space. I had some different ways to transform latitude,longitude and altitude to a cartesian coordinate space, but nothing of them seems to work properly. Currently I'm using ECEF(earth centered), but I also tried different calculations like a combination