I am working on a map application and I have come across an issue with how my tiles are laying while scaling.
Here is a basic look at my structure:
There is obviously a lot more going on, but you get the idea. Now, I scale the Map App Sprite to zoom in. When that scaling occurs, there is a gap between each tile.
You can see the gap where 4 tiles meet here:
I am caching everything as a bitmap. For each Layer (which all extend Bitmap), I have smoothing set to true and pixelSnapping set to PixelSnapping.ALWAYS (pixel snapping shouldn't help here, but it shouldn't hurt either).
Does anyone have any suggestions on how to fix this issue?
(For the sake of completeness, the Map app is built entirely using AS3 and it is embedded in a Flex app)
Using integers for tile x,y locations and calculating those locations correctly is most likely the fix here, unless the images have seams in them!
The code that calculates and sets the x,y locations would be needed to properly pinpoint the issue in the code.
But, also if you are scaling that container sprite, you would want to ensure that you scale so that the width/height of a tile is an integer value.
For example, if you scale your sprite that contains these tiles, the widths/heights of the individual tiles might not always be integers, therefore creating those seams you see.
What you could do in that case is do your scaling by adjusting your width/height values by integer values, taking into account proportions, as opposed to using scaleX and scaleY on your container sprite.
Without seeing your code it's difficult to be sure, but it is possibly just a visual artifact due to scaling - eg: a 250px wide bitmap scaled to 155% should be rendered at 387.5px wide but thats impossible so its rendered at 388px wide - with the 0.5px part rendered as 1px at 50% alpha to give 'appearance' of 0.5px.
Ensuring scaled bitmaps widths/heights are always integers may solve it?
This looks like a rounding error.
Without code it's hard to know: it would be a great asset to you and us if posted a barebones example of your tiling class. In the process of subtraction you may very well discover your solution.
I'd offer that you should test what happens when you scale and algin four 100x100 bitmap images at various fine grain steps, to detect if it's a Flash rendering issue or a defect in your class.
Related
I have images of around 2000 X 2000 pixels. The objects that I am trying to identify are of smaller sizes (typically around 100 X 100 pixels), but there are lot of them.
I don't want to resize the input images, apply object detection and rescale the output back to the original size. The reason for this is I have very few images to work with and I would prefer cropping (which would lead to multiple training instances per image) over resizing to smaller size (this would give me 1 input image per original image).
Is there a sophisticated way or cropping and reassembling images for object detection, especially at the time of inference on test images?
For training, I suppose I would just take out the random crops, and use those for training. But for testing, I want to know if there is a specific way of cropping the test image, applying object detection and combining the results back to get the output for the original large image.
I guess using several (I've never tried) networks simultaneously is a choice, for you, using 4*4 (500+50 * 500+50) with respect to each 1*1), then reassembling at the output stage, (probably with NMS at the border since you mentioned the target is dense).
But it's weird.
You know one insight in detection with high resolution images is altering the backbone with "U" shape shortcut, which solves some problems without resize the images. Refer U-Net.
I've built an game in Libgdx which uses a single FitViewport passed-in to some Screens (Splash/Intro/Game/Menu/Pause etc.).
Each Screen has it's own Stage containing Groups of Actors - I've written a custom render loop to allow Screens to fade-in/out or slide around or render behind each-other - that's all great.
I now want a 'UI' screen which will rotate on smartphones to match their orientation (everything else in the game will NOT rotate).
I can make this work visually by using a TransformMatrix on the SpriteBatch but that doesn't affect the Stage's 'touch' detection (or debugdraw) and it seems there is no way to do this within the Stage (localtoparentcoords allows for rotation and scale but NOT transformation)
Bear in mind that it will not be 'square' (the FitViewport enforces 16x9 ratio) so it needs translation as well as rotation...
Note: I've tried to mess around with cameras but that's the wrong paradigm - cameras are a different view of the same thing - I want different things (transformation and rotated) drawn into the same view!
Note also: I've already started to create my own version of a Screen/Stage class to do this - I think it might be quicker than kicking the existing code into working properly but I'll be surprised if I'm the first person to want this?
I think I've sort-of solved this by stepping-back a bit and looking at how the Stage/Actor system works.
The idea of rotating AND transforming an entire Stage is fraught with complexity - that I could do it at the SpriteBatch level was a distraction which led to a lot of wasted time - sadly.
It was only when I realised that as I was calculating the position of all my UI (Actor) elements relative to either the screen center or a corner, I may as well take the further step of rotating and transforming them at the same time! I also realised that Grouping them ,made this very simple (indeed I could have static and rotating elements simply by using 2 separate Groups!)
Rotating/Moving an Actor will, of course, adjust it's bounding box/touch-area as well - so I now have a proper Stage/Group/Actor model which rotates as the device is rotated - I could be just static information (scores) or even a dynamic menu or an overlay for a 'cue' in a pool game or whatever...
As Edison would have said - I didn't waste 2 days, I just spent 2 days coming up with a large number of ideas which I now know not to work!
Ok I am developing a game using Libgdx and everything was fine until I noticed that when my character moves, its texture becomes slightly blurred at the edges, as if it is blending in with the background in the android version. There seems to be a slight graininess to the image as well which becomes more noticeable when it moves. I THINK these problems might be related to texture filtering, but wanted to come on and ask here to see if anyone had experienced this before. Any insight appreciated.
EDIT: Here is an the image, you can see it's quite grainy on the whole. When it moves the graininess seems move, it is hard to describe, but it looks as if the pixels on the eater are moving relative to each other slightly.
The way I draw it is pretty straight forward the following is called in my render method:
idleTexture = new Texture(Gdx.files.internal("images/GreenGuy.png"));
spriteBatch.draw(idleTexture, x, y*ppuY,width*ppuX,height*ppuY);
All other work I look at does what I am doing, but I am not totally happy with the results. I have tried changing between linear and nearest filtering but this did not change anything. I have also tried just using a smaller image instead of shrinking a large one, but I still get the same problem of the pixels not remaining relatively static while the character is moving.
I've spent several hours trying to work around this issue... when rendering really simple shape (ie. a cube with very low complexity) and using a texture map feature of Three.js, when you rotate the cube the image seems to be distorted while in rotation, and then you can see a line which runs across the surface of the cube which appears as distortion.
http://screencast.com/t/VpSPRsr1Jkss
I understand that is a limitation of canvas rendering - but it seems like this is is a really simple thing to do - rotate a cube that has an image on one face without the distortion.
Is there another canvas library or approach i can take? I was really looking forward to using Three.js for animating some logos and other elemnets - but we can't have distortion like that in a logo or a customer facing landing page.
Thanks for reading, I'm open to suggestions here.
I don't accept increasing the complexity of the face as a solution because that just distributes the distortion through out the face. I really just want to render the image to a flat surface and be able to rotate that object.
The distortion you see is because only two triangles make that plane.
A quick fix is to have more detailed plane.
If you are using PlaneGeometry, increase the number of segments.
If you are using CubeGeometry, increase the number of segments on the plane you need (2 out of 3).
It will take a bit of fiddling to find the best balance between a decent look and optimal performance (as more segments will require more computing). Hopefully for simple scene you'll get away with no major delays.
I am slightly confused about the "correct" way in KineticJS to fill a shape with partial images (crops) from a combined image file (sprite).
Seems like one can either use fillPatternImage with a defined offset, which seems to draw the complete image, albeit with the rest of the image invisible. I only got acceptable performance after I moved those shapes to an extra layer as my sprite is relatively large and the impact of not cropping correctly decreased the fps dramatically.
All alternatives that I have found use the attribute "fill" with another attribute "image" in it, but this seems to result in black background every time.
Using an Image-shape would help, but is rarely usable since my shapes are seldom rectangular.
Since the KineticJS-documentation does not mention specifying crop coordinates ("just" offset, w/o width and height), what is the absolute correct way to do it?
The absolute "absolute correct way" would depend on the platform and your particular code, but.
Have you looked at sprites? http://www.html5canvastutorials.com/kineticjs/html5-canvas-kineticjs-sprite-tutorial/.
To mask simple animated sprites I'd use this in adition of plain javascript after each draw.
context.globalCompositeOperation = 'destination-in';
The performance of drawImage with composite operations is better than drawing shapes manually on webkit, at least.