projection-matrix

Ptoject Tango provides a point cloud, how can you get the position in pixels of a 3D point in the point cloud in meters? I tried using the projection matrix but I get very small values (0.5,1.3 etc) instead of say 1234,324 (in pixels). I include the code I have tried //Get the current rotation matrix Matrix4 projMatrix = mRenderer.getCurrentCamera().getProjectionMatrix(); //Get all the points in the pointcloud and store them as 3D points FloatBuffer pointsBuffer = mPointCloudManager.updateAndGetLatestPointCloudRenderBuffer().floatBuffer; Vector3[] points3D = new Vector3[pointsBuffer.capacity()

I'm using the python OpenGL bindings, and trying to only use modern opengl calls. I have a VBO with verticies, and I am trying to render with an orthographic projection matrix passed to the vertex shader. At present I am calculating my projection matrix with the following values: from numpy import array w = float(width) h = float(height) n = 0.5 f = 3.0 matrix = array([ [2/w, 0, 0, 0], [ 0, 2/h, 0, 0], [ 0, 0, 1/(f-n), -n/(f-n)], [ 0, 0, 0, 1], ], 'f') #later projectionUniform = glGetUniformLocation(shader, 'projectionMatrix') glUniformMatrix4fv(projectionUniform, 1, GL_FALSE, matrix) That

Over the past few weeks I've been attempting to learn the libGDX library. I'm finding it hard, especially for my first endeavor toward game development, to comprehend the system of Camera/viewport relationships. One line of code that I've been told to use, and the API mentions, is: batch.setProjectionMatrix(camera.combined); Despite a good 4 hours of research, I'm still lacking a complete understanding of the functionality of this code. It is to my basic understanding that it "tells" the batch where the camera is looking. My lack of comprehension is depressing and angering, and I'd appreciate

I tried to get horizontal projection using countNonZero() function as below. Mat src = imread(INPUT_FILE, CV_LOAD_IMAGE_COLOR); Mat binaryImage = src.clone(); cvtColor(src, src, CV_BGR2GRAY); Mat horizontal = Mat::zeros(1,binaryImage.cols, CV_8UC1); for (int i = 0; i<binaryImage.cols; i++) { Mat roi = binaryImage(Rect(0, 0, 1, binaryImage.rows)); horizontal.at<int>(0,i) = countNonZero(roi); cout << "Col no:" << i << " >>" << horizontal.at<int>(0, i); } But an error is occured in the line of calling countonZero() function. Error is as follows. OpenCV Error: Assertion failed (src.channels() == 1

Traditionally, in 3D projections, the Y-axis is the axis that represents "up and down". I learned to think of it, with other engines, as that axis being the Z-axis. What I was wondering was whether there is a way in Three.JS to make the Z-axis the "up/down" axis. If so, are there any consequences to it? Here is a diagram of what I want: You could just change the camera rather than the entire coordinate system. For example: var WIDTH = 1024; var HEIGHT = 768; var VIEW_ANGLE = 45; var ASPECT = WIDTH / HEIGHT; var NEAR = 0.1; var FAR = 10000; camera = new THREE.PerspectiveCamera(VIEW_ANGLE,

all, I've got an iphone project that draws a 3D model using OpenGL-ES for a given model view matrix and given projection matrix. I needed to replace 3D model with CALayer, so I put values of model view matrix into CATransform3D structure and assigned it to layer.transform . It worked well, layer was visible and moved on the screen as expected, but after some time I realized that my layers behavior is not precise enough and I should take projection matrix into account. And then a problem appeared: when I simply concatenate two matrices my layer looks odd (it is very small, about 2 pixels, while