> however, I can never seem to get accurate screen coordinates > of the points.
Could you specify what exactly your problem is? Does it not work *at all*, or does it work basically, but points are off by a few degrees? Or does it only work in one orientation of the device (like in landscape mode), and fails in other orientations? Peli www.openintents.org http://code.google.com/p/openintents/wiki/SensorSimulator On Aug 20, 4:55 pm, mscwd01 <[email protected]> wrote: > Hi, > > I want to find the screen coordinates (X,Y) where a point represented > by a latitude/longitude value would appear on the screen if you > pointed your phone at it (much in the same way as Wikitude does). > > Here is my code from my onSensorChanged() method: > > public void onSensorChanged(SensorEvent event) { > Sensor sensor = event.sensor; > int type = sensor.getType(); > > switch (type) { > case Sensor.TYPE_MAGNETIC_FIELD: > mags = event.values.clone(); > isReady = true; > break; > case Sensor.TYPE_ACCELEROMETER: > accels = event.values.clone(); > break; > case Sensor.TYPE_ORIENTATION: > orients = event.values.clone(); > break; > } > > if (mags != null && accels != null && isReady) { > isReady = false; > > SensorManager.getRotationMatrix(R, I, accels, mags); > SensorManager.remapCoordinateSystem(R, > SensorManager.AXIS_X, SensorManager.AXIS_Z, outR); > SensorManager.getOrientation(outR, values); > > azimuth = convert.radToDeg(values[0]); > pitch= convert.radToDeg(values[1]); > roll = convert.radToDeg(values[2]); > > } > > } > > I convert the points I wish to project from their lat/lon spherical > coordinates to Cartesian coordinates and perform a perspective > projection using the roll, pitch and azimuth values returned by the > sensor, however, I can never seem to get accurate screen coordinates > of the points. > > The matrices for roll, pitch and azimuth I use are: > > // pan > double[][] azimuthMat = { > {Math.cos(azimuthValue), -Math.sin(azimuthValue), 0}, > {Math.sin(azimuthValue), Math.cos(azimuthValue), 0}, > {0, 0, 1},}; > > // tilt > double[][] pitchMat = { > {Math.cos(pitchValue), 0, Math.sin(pitchValue)}, > {0, 1, 0}, > {-Math.sin(pitchValue), 0, Math.cos(pitchValue)}, > }; > // roll > double[][] rollMat = { > {1, 0, 0}, > {0, Math.cos(rollValue), -Math.sin(rollValue)}, > {0, Math.sin(rollValue), Math.cos(rollValue)}, > }; > > I also perform the necessary translation of the projection cener and > the point to project e.g: > > // Translate the point > subtract(pointToProject, projectionCenter); > ... where 'pointToProject' and 'projectionCenter' are double arrays > holding the Cartesian coordinates of each location (i.e. camera lat/ > lon and the point to project lat/lon) > > I realise this is quite a complicated question to ask and I haven't > provided all my projection code etc, however if someone feels they can > help me out and may know how to achieve what i'm after - i'll post the > whole code. > > Thanks --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~----------~----~----~----~------~----~------~--~---
