I am trying to detect objects from a given image. From research I just found that we can detect and track an object for the videos using the following process:
private lazy var cameraLayer: AVCaptureVideoPreviewLayer = AVCaptureVideoPreviewLayer(session: self.captureSession)
private func tapGestureAction(recognizer: UITapGestureRecognizer)
{
highlightView.frame.size = CGSize(width: 200, height: 200)
highlightView.center = recognizer.location(in: view)
let originalRect = highlightView.frame
var convertedRect = cameraLayer.metadataOutputRectConverted(fromLayerRect: originalRect)
convertedRect.origin.y = 1 - convertedRect.origin.y
previousObservation = VNDetectedObjectObservation(boundingBox: convertedRect)
}
Can we have similar method like metadataOutputRectConverted for imageView? I am trying to detect the object rect whenever the user taps on that object. How can this be accomplished?
this method to convert the camera output rect ( topleft(0,0) to bottomright(0,1)) to the UI rect. So, I think you do not need to convert it
Related
I'm developing an app with blazor client-side and I need to render a 3D scene.
I have an issue and I guess it is material-related.
I have a composition of parallelepipeds where one of them is fully opaque and the others are transparent.
Depending on the camera angle, the transparent ones completely disappear:
Example where everything is visible:
Example with 2 missing:
Example with all missing:
Code for transparent parallelepipeds
var geometry = new THREE.CubeGeometry(item.xDimension * _scene.normalizer, item.yDimension * _scene.normalizer, item.zDimension * _scene.normalizer);
var material = new THREE.MeshBasicMaterial();
var box = new THREE.Mesh(geometry, material);
box.material.color = new THREE.Color("gray");
box.material.opacity = 0.8;
box.material.transparent = true;
Code for the camera:
var camera = new THREE.PerspectiveCamera(60, width / height, 0.1, 100);
camera.position.set(1.3, 1.3, 1.3);
camera.lookAt(0, 0, 0);
I'm using OrbitControls and every object size is between 0 an 1 (_scene.normalizer is for that purpose)
Do you know why this is happening?
Edit:
I found it being a material depth function issue. Do you know which should I use?
Thanks,
Transparency is tricky with WebGL because a transparent object writes to the depthmap, and then the renderer assumes that subsequent objects behind it are occluded so it skips drawing them. You could avoid this by playing with the material's .depthTest and .depthWrite attributes (see the docs):
box.material.color = new THREE.Color("gray");
box.material.opacity = 0.8;
box.material.transparent = true;
box.material.depthWrite = false;
I am trying to make some sort of gallery app. I would like to display images inside of a ScrollView inside a GridLayout so I used CardView for this and it looks like this:
But when I put ImageView inside each CardView, the CardView spreads and fills the whole ScrollView. Here's a preview:
The CardView is created programatically. Here's the code
fun CreateCardView(ItemCount: Int){
for (i in 1 until ItemCount){
/////////////////////CARD VIEW//////////////////////////////
val card_view = CardView(this)
card_view.radius = 8F
card_view.setContentPadding(8,8,8,8)
card_view.setCardBackgroundColor(Color.LTGRAY)
card_view.cardElevation = 8F
val param = GridLayout.LayoutParams()
param.rowSpec = GridLayout.spec(GridLayout.UNDEFINED, 1f)
param.columnSpec = GridLayout.spec(GridLayout.UNDEFINED, 1f)
card_view.layoutParams = param
val param2 = card_view.layoutParams as GridLayout.LayoutParams
param2.setMargins(10,10,10,10)
card_view.layoutParams = param2
subLayoutGrid?.addView(card_view)
////////////////////////END//////////////////////////////////////
///////////////////////IMAGEVIEW////////////////////////////////
val img = ImageView(this)
val imageparams = WindowManager.LayoutParams(
WindowManager.LayoutParams.WRAP_CONTENT,
WindowManager.LayoutParams.WRAP_CONTENT
)
img.layoutParams = imageparams
img.scaleType = ImageView.ScaleType.CENTER_CROP
img.setImageResource(R.drawable.animaleight)
card_view.addView(img)
////////////////////////END///////////////////////////
}
}
How can I put ImageView inside the CardView without filling the whole ScrollView?
I've already fixed my problem. I've tried to use a 40px x 40px Picture then it worked the way I want to. See the image:
It seems like when you use high resolution Picture, the app cant handle the populating of ImageView in GridLayout.
I am using iOS Charts (Daniel Gindi) to generate graphs in an iOS app and I want to be able to generate a PDF report with those graphs included in the body of the report. Can anyone explain how to go about doing this. Ideally I don't want to generate an image from the UIView that shows in the app because the size/resolution would not be suitable for the PDF document.
As I understand it there are a few options:
use the graphics context for the pdf document to draw the graph on - it's not clear whether this would be possible when using the Charts library
use a UIView somehow to generate the graph and generate a PDF image data from that, embed this image into the pdf report
It seems like option 1 is probably the preferred way to get best resolution/control - somewhat speculative - doing it this way means you should be able to specify the exact position and size and get the correct font sizes, line thicknesses, etc..
Using option 2 means you have to figure out the scaling between a UIView and the PDF page view and I am not sure how these would map to each other.
Can anyone provide any suggestions on the following:
Is it possible to use Charts to generate graphs in a PDF document, and if so how?
If not what other options are there, short of writing custom drawing code.
OK so here is what I have done
Option 1: Using a UIView.layer to render on the PDF CGContect
func drawLineGraph(x: CGFloat, y: CGFloat)->CGRect{
let width = (pageSize.width - 2*kBorderInset - 2*kMarginInset)/2.0 - 50.0
let renderingRect = CGRect(x: x, y: y + 50.0, width: width, height: 150.0)
// Create a view for the Graph
let graphController = LineChartController(rect: renderingRect, building: self.building)
if let currentContext = UIGraphicsGetCurrentContext() {
let frame = graphController.chartView.frame
currentContext.saveGState()
currentContext.translateBy(x:frame.origin.x, y:frame.origin.y);
graphController.chartView.layer.render(in: currentContext)
currentContext.restoreGState()
}
return renderingRect
}
The graphController is just an object that has essentially the same function as the usual parent ViewController that would contain the graph. Sets the graph parameters and data.
Once that has been done the function below is called to render on the PDF page context.
A bit of translation required to put the graphs in the correct position.
Option 2: Drawing on the PDF Page CGContect
And the solution is...ta da...
func drawBarGraph(x: CGFloat, y: CGFloat)->CGRect{
let width = (pageSize.width - 2*kBorderInset - 2*kMarginInset)/2.0 - 50.0
let renderingRect = CGRect(x: x + width + 50, y: y + 50.0, width: width, height: 150.0)
// Create a view for the Graph
let graphController = BarChartController(rect: renderingRect, building: self.building)
if let currentContext = UIGraphicsGetCurrentContext() {
let frame = graphController.chartView.frame
currentContext.saveGState()
currentContext.translateBy(x:frame.origin.x, y:frame.origin.y)
//graphController.chartView.layer.render(in: currentContext)
graphController.chartView.draw(frame)
currentContext.restoreGState()
}
return renderingRect
}
Since the current context is set to the PDF page's context just call the charts draw() function directly passing the frame rectangle.
What have I missed here, can it be this easy ?
You can find a copy of the generated PDF here as well as sample code.
I've put together a custom top-down camera logic script based on Unity3D's ThirdPersonCamera.js script. Everything appears to be working properly, the camera follows the target player on the XZ plane and even moves along the Y-axis as appropriate when the player jumps.
Only the camera isn't looking at the player. So I tried using Transform.LookAt() on the cameraTransform to have the camera looking directly down on the player. This does cause the camera to correctly look directly down on the player, but then movement via WASD no longer works. The player just sits there. Using Spacebar for jumping does still work though.
This doesn't make sense to me, how should the orientation of the camera's transform be affecting the movement of the player object?
The code for my script is below:
// The transform of the camera that we're manipulating
var cameraTransform : Transform;
// The postion that the camera is currently focused on
var focusPosition = Vector3.zero;
// The idle height we are aiming to be above the target when the target isn't moving
var idleHeight = 7.0;
// How long should it take the camera to focus on the target on the XZ plane
var xzSmoothLag = 0.3;
// How long should it take the camera to focus on the target vertically
var heightSmoothLag = 0.3;
private var _target : Transform;
private var _controller : ThirdPersonController;
private var _centerOffset = Vector3.zero;
private var _headOffset = Vector3.zero;
private var _footOffset = Vector3.zero;
private var _xzVelocity = 0.0;
private var _yVelocity = 0.0;
private var _cameraHeightVelocity = 0.0;
// ===== UTILITY FUNCTIONS =====
// Apply the camera logic to the camera with respect for the target
function process()
{
// Early out if we don't have a target
if ( !_controller )
return;
var targetCenter = _target.position + _centerOffset;
var targetHead = _target.position + _headOffset;
var targetFoot = _target.position + _footOffset;
// Determine the XZ offset of the focus position from the target foot
var xzOffset = Vector2(focusPosition.x, focusPosition.z) - Vector2(targetFoot.x, targetFoot.z);
// Determine the distance of the XZ offset
var xzDistance = xzOffset.magnitude;
// Determine the Y distance of the focus position from the target foot
var yDistance = focusPosition.y - targetFoot.y;
// Damp the XZ distance
xzDistance = Mathf.SmoothDamp(xzDistance, 0.0, _xzVelocity, xzSmoothLag);
// Damp the XZ offset
xzOffset *= xzDistance;
// Damp the Y distance
yDistance = Mathf.SmoothDamp(yDistance, 0.0, _yVelocity, heightSmoothLag);
// Reposition the focus position by the dampened distances
focusPosition.x = targetFoot.x + xzOffset.x;
focusPosition.y = targetFoot.y + yDistance;
focusPosition.z = targetFoot.z + xzOffset.y;
var minCameraHeight = targetHead.y;
var targetCameraHeight = minCameraHeight + idleHeight;
// Determine the current camera height with respect to the minimum camera height
var currentCameraHeight = Mathf.Max(cameraTransform.position.y, minCameraHeight);
// Damp the camera height
currentCameraHeight = Mathf.SmoothDamp( currentCameraHeight, targetCameraHeight, _cameraHeightVelocity, heightSmoothLag );
// Position the camera over the focus position
cameraTransform.position = focusPosition;
cameraTransform.position.y = currentCameraHeight;
// PROBLEM CODE - BEGIN
// Have the camera look at the focus position
cameraTransform.LookAt(focusPosition, Vector3.forward);
// PROBLEM CODE - END
Debug.Log("Camera Focus Position: " + focusPosition);
Debug.Log("Camera Transform Position: " + cameraTransform.position);
}
// ===== END UTILITY FUNCTIONS =====
// ===== UNITY FUNCTIONS =====
// Initialize the script
function Awake( )
{
// If the camera transform is unassigned and we have a main camera,
// set the camera transform to the main camera's transform
if ( !cameraTransform && Camera.main )
cameraTransform = Camera.main.transform;
// If we don't have a camera transform, report an error
if ( !cameraTransform )
{
Debug.Log( "Please assign a camera to the TopDownThirdPersonCamera script." );
enabled = false;
}
// Set the target to the game object transform
_target = transform;
// If we have a target set the controller to the target's third person controller
if ( _target )
{
_controller = _target.GetComponent( ThirdPersonController );
}
// If we have a controller, calculate the center offset and head offset
if ( _controller )
{
var characterController : CharacterController = _target.collider;
_centerOffset = characterController.bounds.center - _target.position;
_headOffset = _centerOffset;
_headOffset.y = characterController.bounds.max.y - _target.position.y;
_footOffset = _centerOffset;
_footOffset.y = characterController.bounds.min.y - _target.position.y;
}
// If we don't have a controller, report an error
else
Debug.Log( "Please assign a target to the camera that has a ThirdPersonController script attached." );
// Apply the camera logic to the camera
process();
}
function LateUpdate( )
{
// Apply the camera logic to the camera
process();
}
// ===== END UNITY FUNCTIONS =====
I've marked the problem code section with PROBLEM CODE comments. If the problem code is removed, it allows WASD movement to work again, but then the camera is no longer looking at the target.
Any insight into this issue is very much appreciated.
I figured it out, the issue was with the ThirdPersonController.js script that I was using. In the function UpdateSmoothedMovementDirection(), the ThirdPersonController uses the cameraTransform to determine the forward direction along the XZ plane based on where the camera is looking at. In doing so, it zeros out the Y axis and normalizes what's left.
The cameraTransform.LookAt() call I perform in my custom TopDownCamera.js script has the camera looking directly down the Y-axis. So when the ThirdPersonController gets a hold of it and zeros out the Y-axis, I end up with zero forward direction, which causes the XZ movement to go nowhere.
Copying ThirdPersonController.js and altering the code so that:
var forward = cameraTransform.TransformDirection(Vector3.forward);
forward.y = 0;
forward = forward.normalized;
becomes:
forward = Vector3.forward;
fixed the issue.
I am implementing an application displaying images and messages obtained from .net server. For that I'm adding LinearLayout's with TextView and ImageView dynamically by using for loop.
At first I am getting messages and I'm adding them to the TextView with dummy images placed in ImageView:
for(int i = 0; i < messages.size(); i++) {
FrameLayout f1 = new FrameLayout(this);
LinearLayout l1 = new LinearLayout(this);
LinearLayout l2 = new LinearLayout(this);
im = new ImageView(this);
TextView tv = new TextView(this);
tv.setText(messages.get(i).getmessage());
im.setImageResource(R.drawable.person);
l1.addView(tv);
l2.addView(im);
f1.addView(l1);
f1.addView(l2);
((LinearLayout)findViewById(R.id.LinearlayoutMessage)).addView(f1);
}
After some time I am getting original images. My intention is to replace the dummy images with original ones. To achieve this I'm using imageview.getid() unfortunately I'm getting last id of the imageview. But I need to get each individual imageview id's.
What is the best way of changing dummy images with real ones?
Looks like you need to store each imageView id in a map from each message -> imageView like so:
Map<Message, Long> messageMapping = new HashMap<Message, Long>();
for(int i = 0; i < messages.size(); i++) {
FrameLayout f1 = new FrameLayout(this);
LinearLayout l1 = new LinearLayout(this);
LinearLayout l2 = new LinearLayout(this);
im = new ImageView(this);
TextView tv = new TextView(this);
//add mapping
messageMapping.put(messages.get(i), im.getId());
tv.setText(messages.get(i).getmessage());
im.setImageResource(R.drawable.person);
l1.addView(tv);
l2.addView(im);
f1.addView(l1);
f1.addView(l2);
((LinearLayout)findViewById(R.id.LinearlayoutMessage)).addView(f1);
}
Then when it comes time to lazy load your images into the existing imageViews you simply need to look up the imageView id reference by message mapping:
(Total guess of what your code could look like)
for(int i = 0; i < messages.size(); i++){
Image image = queryServerForImage(messages.get(i).getImageId());
ImageView imageView = ((ImageView)findViewById(messageMapping.get(messages.get(i))));
//some conversion & seteup may be needed to get image into proper format
imageView.setImageBitmap(image);
}
You may be able to do something similar with async tasks. You could span each one in the message ImageView creation loop with the associated resource id and having each asyc task update the ui from the network response.