How to find Index3 of all the fine grid cells associated with a corresponding coarse grid cell?
Terminology used:
Fine Grid : Assume there is a grid with dimensions 10 x 10 x 2
Coarse Grid : This is the coarser version of fine grid which could be of dimensions 5 x 5 x 1.
So for a given grid cell in Coarse Grid, can we find the corresponding fine grid cells associated with it. Is there a ready-made method available or if we need to make our own method, which service should i be using.
For any given Coarse grid cell, we can find the 8 corner points, and now my goal is to find all the fine grid cells which are within the volume made up by those 8 corner points.
Here we are talking about a single grid cell, not entire grid, just to avoid confusion I am mentioning it. This question is for developers who work with Ocean API.
Slb.Ocean.Petrel.Grid has a couple of functions that might help you...
GetPointAtCell
GetCellAtPoint
By using GetPointAtCell on the corner points of your coarse grid you can get the positions of each corner of your cell. Then, you can pass these points into GetCellAtPoint on your fine grid and retrieve the fine-cell-ijk indices for the XYZ corner points you got from your coarse grid. Depending on whether you only want fine cells that are entirely inside the coarse cell or not, you may have to massage the indices a bit, but you get the idea.
(Thanks to Thomas Gehrmann for helping me with the answer)
Related
I have started learning Blender 2.8 as of May-25. Almost 10 years ago, I was using 3dmax v7 but only as a hobby. I want to start doing 3ding again as hobby but got no money to have something that is up to date. So I chose Blender.
Now I have a few questions. I will surely have more questions later. I am still thinking in terms of 3dmax ways.
How do I recenter the object pivot if I accidentally displaced it with MB1 and doing Ctrl-Z is not a solution ?
How do I align vertices to the grid but only using the axis of my choice ? (ex: align on the X axis grid or any other axis of my choice)
how do I group object parts (vertices, faces, ...) as different groups and then working with the group of my choice ?
how can I maximize the view port with one single keys shortcut thus hiding every menus and then once I am done doing what I wanted to on that maxed view, revert back to whatever interface view I was using before ?
how to select anything using a region drawn by mouse movements (meaning selecting without using box or circle or shift, just mouse mouvements)?
Firstly blender 2.80 is under heavy development while making some major changes so can be of varying functionality for now. I would suggest you start learning with 2.79b until 2.80 is finished.
There are several options when it comes to choosing a pivot point, I think what you are referring to is setting the object origin.
There are several snapping options and ways to control transformations. You can limit movement to one axis by pressing it's key while transforming, eg GX will only move along the X axis, you can not move on one axis by adding ⇧ Shift - G⇧ ShiftX will move on Y and Z but not X. To align vertices to one axis is it common to scale to zero one the axis, eg SX0 will scale the verts on the x axis so they all align, in object mode you can do the same as long as you enable manipulate centre points. There are align options available in some addons, like align tools and mesh align plus.
Blender doesn't have vertex grouping and I don't know of any addons that add it. You can assign vertices to a vertex group and use that to select/deselect a collection of vertices.
There are two options to maximise the viewport - ⎈ Ctrl↑ Up arrow will maximize the viewport, the info bar at the top and headers for the view will remain in place or ⎇ AltF10 will make the view full screen also removing the info bar and headers. Also the window layouts are saved as screens which you can make and define to your liking, by saving these screens in your startup blend you can keep them available each time you use blender. The default screens include a 3D only layout.
For lasso select you can hold ⎈ Ctrl while pressing the non-select mouse button to draw an arbitrary region to select items within.
Good morning!
I'm currently trying to create a view similar to this mockup.
I have put down 3 different screen sizes so you can see the issue.
I have a header background image (grey box) with an angled bottom. On the right I want to display an image, which obviously needs to be positioned.
Positioning it horizontally is no issue but how can I position the image vertically? I have it positioned fixed for one screen size but obviously need to make it flexible.
Any ideas? Help would be much appreciated!
David
You can definitely use measure as #rajesh pointed out, or you can use Dimensions. As far as getting the layout consistent across devices, using position absolute and measuring the device height should allow you to get consistency across these devices.
Check out this example I set up, it should be a good starting point at least.
https://rnplay.org/apps/pSzCKg
I am designing a simple music app where the user gets to play instruments i.e. Drums, and the problem that I am facing is with resolutions.
The drums are images, which I have converted them into buttons. Everything looks great at the state that I have designed it.
However, when I switch to other resolution states, the button(image) are distorted, e.g. skewed, scaled, and looks nasty.
I have tried designing or arranging them via selecting 'Enable state Recording', but the specific designs for that state are not being saved.
Have you tried the approaches discussed here? http://msdn.microsoft.com/en-us/library/windows/apps/hh465362.aspx For the actual button sizes, make sure you are not fixing the width/height with pixel values. Use * weighted rows and columns to layout your grids and have the buttons autosize to fill a given cell in the grid. Then match with the appropriate image resource per the article.
Grids are great for dividing up available space but they can't account for changes in aspect ratios. If your items are still set to Stretch (or Fill) then they can end up out of aspect ratio. Another option is to design the entire layout at a fixed size (let's say 1024 x 768 or 1366 x 768) and wrap the entire thing in a ViewBox. ViewBox will scale all elements equally and maintain the aspect ratio, adding letterboxing (or empty space) on the sides / top & bottom if necessary. This might be a better approach for a drum kit.
Hope that helps.
Redid the whole project of designing again.
This time, I put the image inside a specific grid and that made things lot better. :)
OK.
I'm in essense trying to make my own interpretation of the NES hardware, so I can make a game that ideally would resemble what a NES game would look like. I'm currently stuck with how to adjust how to draw the playfield to the video memory (back buffer).
BACKBUFFER
The NES had restrictions on the nametable, or backbuffer. For my example, the backbuffer is 256x240pixels big, or the size of one screen. If I drew this to the TV, it would fill up the screen perfectly. Now, if I drew this to the screen with an offset of X=5, the entire image would be shifted and would wrap around the screen.
For example.....
ORIGINAL, NO OFFSET: DRAWN WITH OFFSET OF X=5:
ABCDEFGHIJK GHIJKABCDEF
DRAWN WITH OFFSET OF X=-5:
FGHIJKABCDE
The screen is split up into squares 8x8 pixels each, totalling 32x30 rows and columns. (256x240 pixels). The offset is represented in pixels - not columns; so in theory, I could offset the screen by 5 pixels and every column would be shifted to the right by five pixels.
LEVEL DESIGN
My stages are made up of screens, containing data that is represented in 16x15 rows and columns, each by 16x16 pixels. This is to emulate how many NES games stored level data - each tile holds info about what should be in each 8x8 block.
E.g.:
AA
BC with A,B,C,D representing what 8x8 graphic should go where
Level design is represented by this as well, with each number being a different screen and - meaning nothing, null.
-----
-123-
---4-
--54-
-----
CHARACTER PLACEMENT
This is easy. I already know how I can determine which table, row, and column my characters are on based on their absolute positioning. I can also determine the relative positioning within the screen.
With this info, I can easily figure out which columns are to the left and right of the character, if any (if the character is at the left side of screen 1, thered be no more level left)
SO HERE'S THE QUESTION DUN DUN DUN
How do I draw my levels to the screen, so that they scroll from one to the next.
It would be relatively easy to draw one full screen at a time, and when the character gets to the edge just flip to another screen.
However, the problem I'm conceptually having is that I need to 'stream' the level data onto the screen. That, lets say the character moves 24 pixels to the right. The BG needs to move as well.
So, I need to adjust the scrolling of the backbuffer by 24 pixels. However, just scrolling alone will cause the screen to wrap over, diplsaying old portion of the level. So, while scrolling I need to make sure to draw new pieces of the level to the back buffer. But before I can do that, I need to figure out which tiles need to get drawn first. And if the person goes 24 pixels to the left, I need to redraw tiles onto the backbuffer and change the offset accordingly as well.
And let's not forget that if the character moves right and there's no more level data to be drawn, there should be no offset but instead the character gets closer to the side of the screen (instead of being centered in the middle of the screen via the X axis).
Basically, I just have a lot of different numbers and values stuck in my mind right now - trying to wrap my head around many concepts and they caused my brain to turn into goo. Anyone have any perspective on how I can approach this?
EDIT: Using VB.Net. C# is applicable as well ( I program in both)
The way the NES did it was with 4 name tables, each 256x240. When you scrolled one off the screen, the adjacent one would scroll on. To get "worlds" bigger than 512x480, you update the name table at the positions that are offscreen.
Generally, a cartridge would have a giant table in ROM with all of the level data, and would track the overall position with 1 or 2 RAM variables. Then when the game scrolled, it would update the RAM variables, use those to lookup the level data table and copy in the new level data into the parts of the name table that were offscreen.
So actually your back buffer should be 512x480, and you only show a 256x240 portion of it.
Have you looked at the disassembly for any NES games that have large scrolling worlds? I think a partial disassembly of Metroid is out there somewhere...
...yeah, found some docs at romhacking.net
Metroid disassembly; not real well commented but with a little effort it shouldn't be too hard to figure it out.
Another disassembly that is commented better.
EDIT: In the 2nd disassembly posted above, look in MetroidGameEnginePage.txt at the "SetupRoom" routine and the "DrawRoom" routine; also the routine at label LEB4D shows how the name table is updated in one case. Also look at the extensive comments above the "GetNameTable" routine. In general, a text search for "name table" throughout the document will get you lots more.
EDIT EDIT: Also at romhacking.net; the memory map for SMB might be useful.
I would set up a grid of image controls and load the levels from a database that stores what column and row each picture is relative to the level. Once the image that represents the game's character gets far enough to the right (you would have to store its location in some module level variables) of the screen you would load the next column of images (while shifting all of the other images one to the left and removing the first column).
I am in the process of making my 2D engine for a Beat'em Up game (Castle Crashers is what I call Beat'em Up or Brawler kind of game ).
I will support 2D sprites and 2D particle emitters. This is all done in the engine now. But I have come to an issue that I would like to ask for advice:
It's about "space" management, what I thought was to do something as this image shows:
alt text http://img337.imageshack.us/img337/9162/spacingprototype1.png
My idea is to make a grid ( Spatial Hash or Grid ), of the ground where my Particle Emitters / 2D sprites will live. In my picture, I have enumerated this slots from 1 to N, (don't have to be 35, it's just for showing purposes ). My idea is to draw the "GameElements" (Sprites/Emitters) in order from 0 to N , ( going from bucket 0 to bucket N ) , so then I will get them to display correctly overlapped on screen (back to forward).
I know this could be done by just comparing the lower Y axis of each Element and performing a "quicksort" too, but having the Grid could allow me to perform Collision Detection in a better way , and if I do something like A* to implement some kind of AI, it could help me too.
If you want to have some sort of optimization for the number of objects you need to test against each other, you might want to think about using a Quadtree
http://en.wikipedia.org/wiki/Quadtree
The idea is to divide the screen up in 4 nodes, placing all items in the node they belong, then divide the nodes you just created up in another 4 if there are sprites/items/whatever in there that need to be tested. Keep doing this until a certain size or amount of items in a node has been reached.
You can then ask the top-node if it contains the item you want to test. This node will then ask the child-nodes if it contains the item, which in their turn will ask their children. This way a large part of the screen can be skipped already (if it's located in child 00, you can skip child 01, 10 and 11). Then you get a list of items you perform more specific collision detection on when it's desired to do so.
If you were to make it visual, it would look a bit like this:
alt text http://geodata.ethz.ch/geovite/tutorials/L2GeodataStructuresAndDataModels/en/images/quadtree.gif
Fire them out to the Z buffer and let that worry about it.
If you find that in the future it is too slow (via profiling obviously) then look at optimizing it.
Take the simplest solution and move on.
Your method fails if you have two sprites occupying the same box in the grid. Suppose you have two enemies both standing in the same box. One stands slightly in front of the other. Which do you draw first? You would need two algorithms - one which divides the sprites into the grid, and the second which looks at the z co-ordinates of all the sprites in a given grid box and draws them based on that value.
A far simpler method is to have a single collection of all sprites. It should store all sprites sorted by their z co-ordinates (from the back of the screen at the head of the list to the front of the screen at the back). Loop through the collection and draw each sprite as it appears. When a sprite moves into or out of the screen (ie. its z co-ordinate changes) you can perform a very simple sort to move that single sprite within the collection. Keep swapping it with the next sprite in the list until the next sprite's z co-ordinate is greater than/less than (as appropriate) the changed sprite's co-ordinate.