coordinate-systems

问题 Closed . This question needs details or clarity. It is not currently accepting answers. Want to improve this question? Add details and clarify the problem by editing this post. Closed 11 months ago . Improve this question How to convert pixel/screen coordinates to cartesian coordinates(x,y)? The info I have on the pictures is (see image): vFov in degrees, hFov in degrees, pixel width, pixel height Basically what I want is to take any pixel on the image, and calculate the relative degrees it

问题 I notice that a lot of drawing APIs have their 0,0 origin at the top left corner, so y actually goes down as it increases. I wonder why is that? Any particular advantage to not working in what I personally consider to be more logical bottom left corner (the origin of a regular x/y grid), which also happens to be the native representation of coordinates in hardware rendering APIs? Or maybe it has something to do with the way scanline rendering or even display refresh goes? 回答1: 2D raster

问题 Let's say I have a small area mapped out using local planar coordinates in meters. e.g. A rectangular warehouse that's 300m x 450m. I use some GPS device to find the WGS 84 lat/lon of one corner of the warehouse. How can I project my plane coordinates onto the WGS 84 geoid to find the lat/lon values for the 3 other corners of the warehouse? I understand this is a complicated problem since values vary on different parts of the earth. Do I need to deal with finding some local coordinate system

问题 Let's say I have a small area mapped out using local planar coordinates in meters. e.g. A rectangular warehouse that's 300m x 450m. I use some GPS device to find the WGS 84 lat/lon of one corner of the warehouse. How can I project my plane coordinates onto the WGS 84 geoid to find the lat/lon values for the 3 other corners of the warehouse? I understand this is a complicated problem since values vary on different parts of the earth. Do I need to deal with finding some local coordinate system

问题 I'm trying to create a cartesian coordinate system (i.e. for coordinate geometry) using chart.js. The documentation actually states "cartesian axes" but I'm not seeing any evidence that such a name is warranted. My chart is as follows: <canvas id="myChart" width="400" height="400"></canvas> <script> var ctx = document.getElementById('myChart').getContext('2d'); var scatterChart = new Chart(ctx, { type: 'scatter', data: { datasets: [{ label: 'Scatter Dataset', data: [{x:-3,y:5},{x:-2,y:0},{x:

问题 How do I flip the y value of an NSPoint to a flipped coordinate space. I have two sources of points, both in global screen space, but one is flipped: one from a screen coordinate space with 0,0 = top left. one from a screen coordinate space with 0,0 = bottom left. I need to flip the second one (bottom left) to be in the same space as the first one, top left. How can I do that on an NSPoint or CGPoint? 回答1: For Mac OSX Cocoa, you can flip the y Coordinate for a view, just override isFlipped to

问题 I am trying to convert some datasets into the same coordinate system (NC2264) NC2264 = 'EPSG:2264' sfd_subs = pd.read_csv(r'FILE_LOCATION.csv') wake_shapes = gpd.GeoDataFrame.from_file(r'FILE_LOCATION.shp').to_crs(NC2264) sfd_subs = gpd.GeoDataFrame(sfd_subs, geometry=gpd.points_from_xy(sfd_subs.Longitude, sfd_subs.Latitude),crs='EPSG:4326') sfd_subs.to_crs(NC2264) print(sfd_subs.crs) The shapefile conversion works perfectly but the 'sfd_subs' remains unchanged. I'm getting no errors. I've

问题 The code below brings the text in the center of x, but i don't know how to calculate the center for the y coordinate... it is not (imgH-h)/2! (The right y-coordinate is -80) from PIL import Image, ImageDraw, ImageFont font= './fonts/BebasNeue-Regular.ttf' color = (255, 244, 41) text = 'S' img = Image.new('RGB', (500, 500), color=(255, 255, 255)) imgW, imgH = img.size fnt = ImageFont.truetype(font, 600) d = ImageDraw.Draw(img) w, h = d.textsize(text, fnt) nullH = (imgH-h) print(imgH, h) d.text

问题 I have CVPixelBufferRef from an AVAsset . I'm trying to apply a CIFilter to it. I use these lines: CVPixelBufferRef pixelBuffer = ... CVPixelBufferRef newPixelBuffer = // empty pixel buffer to fill CIContex *context = // CIContext created from EAGLContext CGAffineTransform preferredTransform = // AVAsset track preferred transform CIImage *phase1 = [CIImage imageWithCVPixelBuffer:pixelBuffer]; CIImage *phase2 = [phase1 imageByApplyingTransform:preferredTransform]; CIImage *phase3 = [self

问题 I have CVPixelBufferRef from an AVAsset . I'm trying to apply a CIFilter to it. I use these lines: CVPixelBufferRef pixelBuffer = ... CVPixelBufferRef newPixelBuffer = // empty pixel buffer to fill CIContex *context = // CIContext created from EAGLContext CGAffineTransform preferredTransform = // AVAsset track preferred transform CIImage *phase1 = [CIImage imageWithCVPixelBuffer:pixelBuffer]; CIImage *phase2 = [phase1 imageByApplyingTransform:preferredTransform]; CIImage *phase3 = [self