Im am creating a game where the character will be able to run about a prison only able to see walls and characters within its line of sight. The following screenshot is the desired effect.
Desired effect
However I have a problem where some walls are covered up due to the top corner not being visible as seen here.
Bottom right corner wall is covered
I am using the following code
checkPlayersx = x
checkPlayersy = y
if(!collision_line(checkPlayersx,checkPlayersy,obj_player.x,obj_player.y,obj_wall,1,0)
When looking at the bottom right block, the field of view is obstructed by the top and left tiles. You may have to find an other way to trigger this block.
You might encounter this issue with some other angular blocks too. What you could do is create a new object, that would have as parent the standard wall bloc, but it would take the ID of the adjacent blocks and light up if one of the adjacent blocks it lit up.
To detect the adjacent blocks during creation, it will be essential to create this block after it's neighbors. You can use the instance_nearest() function to detect them.
But the technique I would use is slightly different. I would create a cross-shaped sprite that would, when put in place of the block, cover the centers of the adjacent blocks, and use precise collision checking. At the creation of the wall, I would replace the wall sprite by the cross, and detect collisions with the adjacent walls. All adjacent walls IDs would be stored and checked every step for lighting in order to trigger the lighting of the wall. Then I would go back to the normal wall sprite, and voilà !
Hoping this helps.
Related
I am attempting to come up with a quick and efficient means of translating a 3d mesh into a projected AABB. In the end, I would like to accomplish something similar to figure 1 wherein only the area of the screen covered by the cube is located inside the bounding box highlighted in red. ((if it is at all possible, getting the area as small as possible, highlighted in blue, would increase efficiency down the road.))
Figure 1. https://i.imgur.com/pd0E20C.png
Currently, I have tried:
Calculating the point position on the screen using camera.unproject_position(). this failed largely due to my inability to wrap my head around the pixel positions trending towards infinity. I understand it has something to do with Tan, but frankly, it is too late for my brain to function anymore.
Getting the area of collision between the view frustum and the AABB of the mesh instance. This method seems convoluted, and to get it in a usable format I would need to project the result into 2d coordinates again.
Using the MeshInstance VisualInstance to create a texture wherein a pixel is white if it contains the mesh instance, and black otherwise. Visual instances in general just baffle me, and I did not think it would be efficient to have another viewport just to output this texture.
What I am looking for:
An output that can be passed to a shader informing where to complete certain calculations. Right now this is set up to use a bounding box, but it could easily be rewritten to also use a texture. It also could be rewritten to use polygons, but I am trying to keep calculations to a minimum in the shader.
Certain solutions I have tried before have worked, slightly, but this must be robust. The camera interfacing with the 3d object will be able to move completely around and through it, meaning at times the view will be completely surrounded by the 3d model with points both in front, and behind.
Thank you for any help you can provide.
I will try my best to update this post with information if needed.
I'm building a game in which I can enter a building, which I'm handling via states. In other words, when my character overlaps with the door, the program starts a new state in which the interior of the building is built. Now, I want the interior to have smaller dimensions than the world, so I want to change the game size when I start this new state.
I tried this:
create: function()
{
//game size was 1000x700, I want to scale it to 700x450
game.width = 700;
game.height = 450;
//rest of creation code...
}
I also tried things like changing camera bounds, world bounds, world size, but method above shows the most promise.
The problem, however, is that the resize for some reason does not show until I click away from my browser tab and back. Calling game.width in the console yields 700 at all times, but it doesn't show it as such until tabbing out and back.
On top of that, the contents of the game (floor, furniture) are scaled down when the game resizes, defeating the purpose. I don't understand why it would, since there's no scaling anywhere in my code.
Any help would be greatly appreciated.
Edit:
I just saw that you were the one asking the question I linked to, so I guess the question is solved :D
I had a similar problem some time ago. As you described yourself: what you are doing is a resize! So the game resizes itself which means the same as re-scaling everything in the game.
if you want to cut the game smaller you can simply use
game.scale.setGameSize(700, 450);.
(see this post if you need more information)
As additional information: I later had problems with cutting the game size equally on all sides, so if you should come to face the same problem, have a look at this post
I have a limited area (screen) populated with a few moving objects (3-20 of them, so it's not like 10.000 :). Those objects should be moving with a constant speed and into random direction. But, there are a few limitation to it:
objects shouldn't exit the area - so if it's close to the edge, it should move away from it
objects shouldn't bump onto each other - so when one is close to another one it should move away (but not get too close to different one).
On the image below I have marked the allowed moves in this situation - for example object D shouldn't move straight up, as it would bring it to the "wall".
What I would like to have is a way to move them (one by one). Is there any simple way to achieve it, without too much calculations?
The density of objects in the area would be rather low.
There are a number of ways you might programmatically enforce your desired behavior, given that you have such a small number of objects. However, I'm going to suggest something slightly different.
What if you ran the whole thing as a physics simulation? For instance, you could set up a Box2D world with no gravity, no friction, and perfectly elastic collisions. You could model your enclosed region and populate it with objects that are proportionally larger than their on-screen counterparts so that the on-screen versions never get too close to each other (because the underlying objects in the physics simulation will collide and change direction before that can happen), and assign each object a random initial position and velocity.
Then all you have to do is step the physics simulation, and map its current state into your UI. All the tricky stuff is handled for you, and the result will probably be more believable/realistic than what you would get by trying to come up with your own movement algorithm (or if you wanted it to appear more random and less believable, you could also just periodically apply a random impulse to a random object to keep things changing unpredictably).
You can use the hitTest: method of UIView
UIView* touchedView=[self.superview hitTest:currentOrigin withEvent:nil];
In This method you have to pass the current origin of the ball and in second argument you can pass nil.
that method will return the view with which the ball is hited.
If there is any hit view you just change the direction of the ball.
for border you can set the condition for the frame of the ball if the ball go out of the boundary just change the direction of the ball.
For those of you who have used bullet physics...
I read and ran the hello world example http://www.bulletphysics.org/mediawiki-1.5.8/index.php/Hello_World,
and I am confused where to go next.
The hello world tutorial consisted of a btStaticPlaneShape and a btSphereShape, both rigid bodies. The sphere bounced on the static plane shape no problem.
However, I when I make another sphere at a different position, Bullet does not record collisions between the two sphere shapes, but it both automatically bounce off of btStaticPlaneShape. What kind of internal magic causes the btStaticPlaneShape to automatically bounce objects that collide with it?
Is there a setting in Bullet that automatically bounces objects off of each other after colliding? Or do you have to manually test for collisions and apply the resulting forces yourself?
Thanks.
You may have inadvertently created the spheres in a state where Bullet doesn't think they're supposed to be able to collide with each other. If you stick mostly to the defaults, and just add another sphere to the Hello World program, Bullet should notice and react to their collisions. They won't actually bounce unless you also modify Hello World to set their restitution to something greater than zero, but they will collide. For example, I added a second sphere directly above the first (by putting a for loop around the code block that creates the sphere, and using the loop variable to determine the origin y value) and extended the simulation so it runs long enough for them both to reach the plane. The first lands on the plane and rests there, the second lands on the first and rests there.
If this doesn't help, then posting some of your code is probably a good next step.
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).