My iOS Views are off half a pixel? - ios4

My graphics are looking blurry unless I add or subtract a half pixel to the Y coordinate.
I know this is a symptom that usually happens when the coordinates are set to sub-pixel values. Which leads me to believe one of my views must be off or something.
But I inspected the window, view controller and subviews, and I don't see any origins or centers with sub-pixel values.
I am stumped, any ideas?

See if somewhere you are using the center property of a view. If you assign that to other subviews, depending on their sizes they may position themselves in half pixel values.
Also, if you are using code to generate the UI I would suggest using https://github.com/domesticcatsoftware/DCIntrospect. This tools allows you in the simulator to look at all the geometry of visible widgets. Half pixel views are highlighted in red vs blue for integer coordinates. It helps a lot.

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How to make image fit screen in Godot

I am new in godot engine and I am trying to make mobile game (portrait mode only). I would like to make background image fit screen size. How do I do that? Do i have to import images with specific sizes and implement them all for various screens? If I import image to big, it will just cut out parts that don't fit screen.
Also, while developing, which width and height values should I use for these purposes?
With Godot 3, I am able to set size and position of sprite / other UI elements using script. I am not using the stretch mode for display window.
Here is how you can easily make the sprite to match viewport size -
var viewportWidth = get_viewport().size.x
var viewportHeight = get_viewport().size.y
var scale = viewportWidth / $Sprite.texture.get_size().x
# Optional: Center the sprite, required only if the sprite's Offset>Centered checkbox is set
$Sprite.set_position(Vector2(viewportWidth/2, viewportHeight/2))
# Set same scale value horizontally/vertically to maintain aspect ratio
# If however you don't want to maintain aspect ratio, simply set different
# scale along x and y
$Sprite.set_scale(Vector2(scale, scale))
Also for targeting mobile devices I would suggest importing a PNG of size 1080x1920 (you said portrait).
Working with different screen sizes is always a bit complicated. Especially for mobile games due to the different screen sizes, resolutions and aspect ratios.
The easiest way I can think of, is scaling of the viewport. Keep in mind that your root node is always a viewport. In Godot you can stretch the viewport in the project settings (you have to enable the stretch mode option). You can find a nice little tutorial here.
However, viewport stretching might result in an image distortion or black bars at the edges.
Another elegant approach would be to create an image that is larger than you viewport and just define an area that has to be shown on every device no matter whats the resolution. Here is someone showing what I am meaning.
I can't really answer your second question about the optimal width and height but I would look for the most typical mobile phone resolutions and ratios and go with that settings. In the end you probably should start with using the width and height ratio of the phone you want to use for testing and debugging.
Hope that helps.

How to control KML icon drawing order, top to bottom

I'm displaying many overlapping icons in a Google Earth tour. I'd like to control (or at least understand) the order in which the icons are drawn (which one shows on "top"). Thanks!
PS. Non solutions attempted: Using gx:drawOrder (it applies to overlays, but not icons). Using AnimatedUpdate to establish the order chronologically. Using the order in which you introduce the placemarks to establish their drawing order.
Apparently Google Earth draws the features in groups by type: polygons, then ground overlays, followed by lines and point data where drawOrder is applied only within a group. ScreenOverlays are drawn last so they are always on top.
If you define gx:drawOrder or drawOrder on a collection of features, it only applies to the features of the same type (polygon and other polygons) not between different types.
That is the behavior if the features are clamped to ground. If features are at different altitudes then lower altitude layers are drawn first.
Note that the tilt angle affects the size of the icon and as the tilt approaches 90 degrees, the size of the icon gets smaller. The icon is at largest size when viewed straight-down with 0 degree tilt angle.

libgdx - how to change the color of a pixel in a TiledMapTile?

I succeeded in retrieving the exact tile my player is on, at runtime when walking around the tiledmap. I'd like now to add some alpha marks on the terrain when passing over, and to do that I need to modify the color of some pixels of the tile.
I really don't know how to do it right now.. any hints?
thanks.
You probably want to draw decorations on top of the tiles, rather than modifying the tiles themselves. The tile images are shared across all cells using a tile, so if you modify the tile itself you would see the change everywhere it was used. Further, modifying the texture is a relatively expensive operation that you probably should try to avoid.
To draw on top the tiles, you might draw additional sprites, or use a custom shader.

SVG plot from point-value pairs

I need to write some code (for a web.py webapp with a straight-HTML/JS client) that will generate a visual representation of a set of point-values. Each point has an X and Y coordinate, and the value is an integer. If I can use SVG to do this, then I can scale the image client-side with no extra code. Can I actually do this? I am concerned about a couple of things:
The points don't necessarily have any relation to each other. They aren't necessarily in a grid, nor can we say how many points are nearby, etc.
Gradients are primarily one-direction, and multiple gradients on the same shape seems to be a foreign concept.
Fills require an existing image, at which point, I'd be better off generating the entire image server-side anyway.
Objects always have a layering, even if it isn't specified, which can change how the image is rendered.
If it helps, consider a situation where we have a point surrounded by 5 others, where one of them is a bit closer than the others (exact distances and sizes can be adjusted). All six of the points have different colors (Red, Green, Blue, Cyan, Magenta, Yellow, with red in the center and Yellow being slightly closer), and the outer five points are arranged roughly in a pentagon. Note that this situation is not the only option, just a theoretically possible situation.
Can I do this with SVG, or should I render an image server-side?
EDIT: The main difficulty isn't in drawing the points, it is in filling the space between the points so that there is no whitespace, and color transitions aren't harsh/unpredictable if you know the data.
I don't entirely understand the different issues you are having with wanting to use svg. I am currently using the set up you are describing to render X-Y scatter plots and gaussian curves and found that it works great.
Regarding the last point about object layering, you have to be particularly careful when layering objects with less than 100% opacity which are different colors. The way the colors "add" depends on the order in which you add the objects to your svg drawing.
Thankfully you can use different filters to overlay the colors without blending them. Specifically I am using the FeComposite filter element. There is a good example of its usage here:
http://www.w3.org/TR/SVG/filters.html#feCompositeElement

Problem in M3G rendering in J2ME

I have made 3 planes and positioned them in a way that they make a corner of cube. (For some reasons I don't want to make a cube object). The 3 planes have 3 different Texture2Ds with different images. The strange problem is when I render the 3 objects and start rotating the camera, in some perspectives some parts of these 3 planes don't get rendered. For example when I look straight at the corner a hole is created which is shaped as a triangle. This is the image of the problem in a netbeans emulator:
alt text http://www.pegahan.com/m3g.jpg
I put the red lines there so you can see the cube better.
The other strange thing is that the problem resolves when I set the scale of the objects to 0.5 or less.
By the way the camera is in its default position and the cube's center is at (0,0,0) and each plane has a width and height of 2.
Does anyone have any ideas why these objects have a conflict with each other and how could I resolve this problem.
Thanks in advance
looks like classic case of "box bigger then camera far clipping plane" error :)
since I don't know anything about m3g I can just point you to google that.

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