The Art of Random Cityscapes in MakeCode for Minecraft

 

This MakeCode for Minecraft program is called “Cityscape.” Zillions of cityscapes can be generated by customizing input parameters. A few cityscapes generated by t he program are shown in this blog post.
tall city

ice city.png

dark down

Idea

I had the idea for generating random cityscapes as I was developing The Art of Random Walks in MakeCode for Minecraft.  Essentially, the idea was that instead of placing blocks at each random step, the program would place a building built with a random block with random height, width and depth (depth here means how far back). The program would then move to another  location a random distance from the prior building. It would then place another building, and so on, until the specified number of buildings were placed. The random selections would all be within player specified limits. Optionally, the program would place “ground” of a player-specified block within a rectangle around the city.

city 200 bldg

Customizing Cityscape

Cityscape’s has many options. Such flexibility is marvelous for an experienced player, but can be confusing for a first timer. This is a challenge frequently faced  by software designers. In this case, the solution was to have a default for every option so that a player need only type “city” in the command window to generate a beautiful, probably unique, cityscape. Typing “city” again, generates another city that likely will appear very different from the first, and so on, until the player decides that something a little different would be nice — time to start exploring the options.

Cityscape’s options are specified as follows:

  1. As the values of the parameters in the functions “default_params” and “custom_params.”
  2. As the three arguments to the on-chat “city” command, which starts the program.
  3. As the blocks specified in the block arrays.

Default and Custom Parameter Functions.

Both the default and custom parameter values, which are set in their respective functions,  can be changed.  I suggest having the values in “default_params” be the ones you use most often and the params in “custom_params” be experimental. I also save sets of favorite values by copying them to a scratch area of the program so that I can drag them in and out of the parameter functions.

Cityscape parameters include the following (in the order shown in the param functions):

  • the number of buildings
  • the block array to be used for buildings
  • whether or not to do a compass
  • the ground block to be used in the rectangle surrounding the city
  • the block to be used under the ground block. This is useful if a glass block is used for the ground.
  • foundation block to be used under each building. This is replaced if a new ground is laid.
  • whether a random block is to be used for the ground
  • whether all buildings are to be cubes
  • lower and upper limits for building height
  • lower and upper limits for building width
  • lower and upper limits for building depth (how far back)
  • the maximum distance from one building to another

parms code.png

In the left cityscape below,  all dimensions are set to 1 with a move range of 3. This cityscape illustrates the random walk from the origin, which is indicated by the clear glass block above the lower right TNT block. The right cityscape below has a move range of 0, which means all buildings, which have varying dimensions,  are  built in the same place.

A Function to Verify Parameters

The function “verify_params” checks the parameters for correct values. If one is wrong, for example, a negative value for width, the program will say a message and stop. The last verification in the routine is to check whether the fill command volume limit of 32,768 will be exceeded for any building. This is done by calculating the largest possible volume,  which is calculated as the product of the three variables height limit, width limit  and depth limit.

verify code

color sym city

Blocks from Which Buildings Are Constructed

Building blocks are  specified by the variable “which_array” in the parameter routines above. The values can be 1, 2, 3 or 4. This value can be overridden by an  on-chat “city” command argument. The values 1, 2, 3 or 4 specify, in order, one of the following arrays:

  1. jewel_array,
  2. black_array,
  3. other_array and
  4. an array constructed from all three of the above arrays.

Each of these arrays can have any number of blocks and can contain any type of Minecraft block from which a building can be constructed. The names of the arrays cannot be changed unless they are also changed in the code that reference the arrays. The variable “this_array” is set to the array that is selected by the “which_array” parameter or argument. For building construction, blocks are randomly selected from “this_array.”

array code

on-chat “city” Command Arguments

The on-chat “city” command (see below)  has three arguments.

city args

If num1 is 0, default_params are used. If 1, custom_params are used. A valid num2 overrides the number of buildings provided in default or custom parameters. A valid num3 overrides the array of blocks to be used.

blue city

Using Cityscape

The on-chat “city” command is the main command. It generates a cityscape according to the previously set parameters and arrays, which may have been overridden by the command’s arguments (see above).

The on-chat “view” command moves through views of the city from 20 different vantage points, including 4 sides, 4 corners, over the origin and over center of rectangle. For each of these  2 different heights are used. The on-chat command “s” will stop movement at the current view. The argument num1 to view is the number of seconds to pause at each view, default 3.

The Code

The left third of Cityscape’s code has to do with the inputs that tailor the program to generate an near-endless variety of cityscapes. The middle third, which is launched with on-chat “city” command,  is the guts of the program and actually constructs the city building by building within the bounds of the input parameters. The right third of the program is primarily that launched by the “view” command, which assists the player in looking at the city from various vantage points.

All Code

on-chat Command “city” Starts the Program

The on-chat “city” command defines the main flow of the program in the following steps:

  1. Processes arguments to
    • choose between default and custom parameters,
    • optionally, override number of buildings and
    • optionally, override the array of blocks used in building construction.
  2. Initializes variables, sets origin and, optionally, launches an on-chat to draw a compass.
  3. Uses a repeat block for the following:
    • calls “do_one_building” function to construct a building and
    • calls “get_new_rposition” to pick random position for next building.
  4. Adjusts height of origin marker to be taller than highest building and moves player to above origin.
  5. Calls “build_ground” to create rectangle at ground level.

city code

Function to Do One Building

The “do_one_building” function does the following:

  1. picks random height, width and depth.
  2. calls function to pick block to be used.
  3. uses fill block to create hollow building.
  4. uses fill block to lay foundation of building.
  5. calls function to update minimum and maximum X and Z.

do one bldg code

Function to Get New Random Position

The position of the next building is selected as a random position between the current building’s position plus {minus the move range, 0, minus the move range} and the current building’s position plus {move range, 0, move range}. Simply put, the new building can be any direction up to a distance of  move range from the current position.

get new position code

Function to Pick the Block for Building Construction

The “pick_block” function chooses a random block from the “this_array” array. It also call the function “give_flint_if_needed” to give the player a flint-and-stone item if the block is TNT.

pick block code

Function to Give Player Flint and Steel Item If Block Is TNT

This function gives the player a flint-and-stone item if “this_block” is TNT and the item had not been previously given in this run of “city.” This function is called when a new building block is chosen and also when the foundation block is selected.

give flint

blown up

Functions to Initialize and Finalize Origin Marker and Player Position

Origin marker is a tower of clear glass blocks that is a bit higher than the tallest building. It marks the place of the first building. I use it to view the direction that the random sequence of buildings developed. Initially, the marker is at the maximum height that a building can be. Finally, it is adjusted to be just above the actual highest building. The on-chat “no” command erases the origin marker. This is useful for those situations where the origin marker detracts from the view of the city.

origin marker

Functions to Keep Track of Minimum and Maximum X and Z coordinates

Maximum and minimum X and Z coordinates are updated with each building so that, in the end, the ground can be placed under the city with the same distances from buildings on all sides. Most of the view points are on the perimeter of the rectangle surrounding the city.

min max XZ code

Function to Do Ground Rectangle

This function uses the minimum and maximum X and Z coordinates to define a rectangle. Within that rectangle, grass is replaced by a block, which is either a random block or a block supplied as a parameter in either default or custom parameters functions. An underground block is also placed below the ground. This is useful when the ground is transparent.

do ground code

on-chat “view” Command Helps the Player in Appreciating Her Handiwork

After a cityscape is generated, the player may want to look at it from various vantage points because the view can be very different from various directions. Moving around a city can be tedious; therefore, automation to the rescue. The on-chat command “view” moves the player through 20 positions, pausing to allow time to view each one. The number of seconds to pause is specified to num1, which defaults to 3 seconds. If a particular view is spectacular, an “s” on-chat command stops movement to the next view.

view code

Function to Calculate the Positions for Viewing a Cityscape

The ground plane positions from with views are provided are shown by the drawing below. Minimum and maximum X and Z are used to do the calculation in the function that initializes the view positions array.

drawing directions

calc view positions

Note that, as far as I know,  arrays of positions are an documented feature of MakeCode for Minecraft.

Other Code Used by Cityscape

Two other pieces of code are used by Cityscape:

  • compass and
  • a function to convert a number on-chat argument  to a Boolean array.

This version of compass is particularly fast and flexible. It will be described in my next block post.

compass

This handy little function was motivated by the fact I needed to use several Booleans arguments to an on-chat command. It will be documented in a soon-to-come blog post.

bits

flat world

This code assumes a flat world such as that described in MakeCode for Minecraft Sandbox World: Make It Flat and Simple.

up black city.png

Get the Code

Cityscape code is shared on Code Connection at this URL

https://makecode.com/_MXigqm5HTdev

To get and use the code, follow these steps.

Click the Import button import button , which is upper right in the Code Connection window just below the banner. This will open the window shown below.
Import choices

Click the Import URL button Import URL, which is on the right, to open the window shown below.

Import Copy link

Paste the URL supplied for the program you want to use in the space under the text “Copy the URL …”
import url with url

Click the Go ahead! button go ahead button.

The next window you will see will be the MakeCode window with the code downloaded from the URL. At this point, you can treat it like any other code, e.g., run it, save it locally, modify it, publish your changes or whatever else your heat desires.

We have tested several other methods of downloading the code using the URL, for example, pasting the URL in a browser. No joy. For more detailed instruction see our post How to Use Shared MakeCode on Microsoft Code Connection for Minecraft.

gray city.png

red on black down

black on cyan city

down-pink.png

down green city.png

down city.png

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Coordinates Tutor in MakeCode for Minecraft

 

main screen

We recently developed a game to demonstrate a player’s knowledge of MakeCode Minecraft coordinates. Soon as The Girl started testing it, we realized that a more tutorial program was needed to assist in learning coordinates. Coordinates Tutor — this program — was born..

How to Play Coordinates Tutor

After the user types run in the command window, the Coordinates Tutor will move to a new, pristine  world location, print a compass in the sky for the player’s reference, place a grid of blocks with a cyan glass block at the origin, which is the variable name we give to the 0 0 point in the grid where the X and Z axes intersect.

After initialization, the program will display the left scene then the right to remind the player that in MakeCode Minecraft coding, a coordinate  X is east, Z is south and Y is up. We do not use Y here because it is always the same.

{  X  Y  Z  }.

The positive X axis is east. If one thinks of herself, the player, as facing east, south will be on her right, north on her left, and west behind. Of course, the values X and Z can be negative as well as positive. A negative X is west and a negative Z is north.

When the right scene — {  E   S  } —  is displayed, Coordinates Tutor is waiting for the user to break any block in the grid. Please, break just one block.

broken block

After a block is broken, question marks will flash during the varying time that it takes for the program to search the grid to find the broken block.

When the program finds the broken block, the coordinates of the block will be printed between the brackets. The  broken block will be replaced with a green one, except for the origin block, which will be restored to a cyan block. The green block shown below is at coordinates { – 2 –  2 }.

coor display

At this point, the user may break another block and the program repeats. Coordinates Tutor is patient allowing a user to break blocks until she has absolutely mastered Minecraft coordinates. Then it is time to play Coordinates Game, which works in reverse: that is, when a coordinate is displayed, the user must break the block at the corresponding position on the grid.

The MakeCode Code

The Code Assumes a Flat World

This code assumes a flat world such as that described in MakeCode for Minecraft Sandbox World: Make It Flat and Simple.

Coordinates Tutor Starts with the Run Command

The on-chat run command initializes the program. The steps are:

  1. Teleport the player to an unused part of the world.
  2. Set the variable origin, which will be used as the reference position for all actions as well as the center of the coordinates grid.
  3. Set a position in the sky to be used as left reference point for the coordinate print area.
  4. Run the on-chat command compass to print E, S, W and N in the distant sky. compass runs while the code after it continues because it is an on-chat, not a function.
  5. Run the on-chat command brackets to print squiggly brackets on the left and right sides of where the coordinates will be printed.
  6. Call the function canvas to draw the grid for the coordinates.
  7. Call the function flashXZES, which will display X Z then E S, inside the brackets. This reminds the  player that the left coordinate is X and the right Is Z, or, equivalently, E and S.

run code

The Action Is in the Broken Events

When the player breaks a white, green or cyan stained glass block, which defines the grid, an on-broken event occurs, which for all three events results in the doBrokenEvent being run.

The doBrokenEvent function does the following:

  1. Sets the Boolean variable air_found to false. This variable will be set to true in the function findAir when the broken block is found.
  2. Set nPrints to 0. This variable will be incremented by 1 in one of the print commands launched by the run-chat flash_q.
  3. Launch chat command flash_q, which flashes questions marks inside the coordinate brackets until air_found is set to true in the findAir function.
  4. Call function findAir, which returns only after the broken block is found at which time it runs the chat command postCoordinates.
  5. The chat command postCoordinates prints the coordinate that was found, which is the coordinate of the broken block. postCoordinates is run as a chat, not a function, so that the on-broken event can complete. Although not required, this is neater than having the possibility of a second on-broken event occurring before the prior one has completed.

on break code

Searching for Air

The findAir function, searches the grid starting at coordinate  { -5  -5 } and searching to { 5  5 } for a position in the grid that is air instead of the glass block that was broken. To do the test, it uses the function testTryPositoin to determine air or not. The variable air_found was set to false before the function findAir was called. If air is found, the function testTryPosition sets air_found to true.

find air code

The function testTryPosition tests the Minecraft position to determine whether or not an air block is at that position. If it is not air, it returns doing nothing as air_found is already false. If air is found, it sets air_found to true and sets the airPositoin as well as air_X and air_Z. Note that airPositon has origin added because the Minecraft position is need to place the green block. However, air_X and air_Z are relative to origin; that is they are the coordinates on the grid, e.g. { ,-5  2 } because these variables will be used in posting the coordinate at which air was found. A green glass block is placed at the position at which air was found.

test try position code

The MakeCode Bug that Wasn’t

While coding testTryPosition, I became convinced that there was a MakeCode bug in testing position variables for equality. After some time trying the understand and prove the bug, which included writing a program to test for the bug in a less complex situation, I realized, as I have so many times before, that the bug was in my understanding of position variables. I will not go into the detail here, but take my word for it — if  you want to test a calculated position variable against another, test that all individual coordinates {X Y Z} pairwise for equality instead.

Print the Broken Block Coordinate

postCoordinate is a simple on-chat command that, if the broken block was found, prints the coordinate between the brackets. If the broken block was not found, which should never happen,  it prints red question marks between the brackets. Most of the code is to adjust the text for whether or not X and Z are negative.

post coordinates code

Simultaneous, Oscillating Print Until … Something Happens

I couldn’t resist explaining how the question marks print at the same time and are reprinted in another color block until the broken block is found. To review this short vid show this working.

The key to the simultaneity is using on-chat commands instead of a function or just doing the print blocks inline.  The changing colors are enabled by the variable nPrnts, which is incremented each time through the print blocks. Because the print blocks are run more or less simultaneously, nPrints must be incremented in only one of the print blocks; otherwise, the colors would get out of sync. The print blocks are in a while loop that tests air_found, which when true,   the prints stop enabling the coordinate of the broken block to be printed in the same spaces.

print q flasher code

Get the Code

Coordinates Tutor  code is shared on Code Connection at this URL

https://makecode.com/_d7PAhvEH98iy

To get and use the code, follow these steps.

Click the Import button import button , which is upper right in the Code Connection window just below the banner. This will open the window shown below.
Import choices

Click the Import URL button Import URL, which is on the right, to open the window shown below.

Import Copy link

Paste the URL supplied for the program you want to use in the space under the text “Copy the URL …”
import url with url

Click the Go ahead! button go ahead button.

The next window you will see will be the MakeCode window with the code downloaded from the URL. At this point, you can treat it like any other code, e.g., run it, save it locally, modify it, publish your changes or whatever else your heat desires.

We have tested several other methods of downloading the code using the URL, for example, pasting the URL in a browser. No joy. For more detailed instruction see our post How to Use Shared MakeCode on Microsoft Code Connection for Minecraft.

Using Minecraft Blocks as Buttons: Block-by-Block Tutorial Video in MakeCode for Minecraft

 

main

Strategy

The strategy for using Minecraft blocks as buttons to control a program is:

  1. Place the buttons on the screen in a place convenient to the player.
  2. In the block on-broken event, use the code that would have been in a on-chat command to do a sequence of actions,
  3. Replace the broken block with another of the same kind.

MakeCode Code

We modified the existing program described in Handy Timer — Block-by-Block Tutorial Video in MakeCode for Minecraft , to illustrate using Minecraft blocks as buttons. Only the changed code is described here.  This code assumes a flat world such as that described in MakeCode for Minecraft Sandbox World: Make It Flat and Simple.

The placeButtons Function

The placeButtons function does exactly what its name implies: it places each button that will be used in lieu of an on-chat command. I like to place the buttons in front of the player within easy reach so that the player need not move to break a block (click a button). In this case we placed red concrete to do the same thing as the stop on-chat command, yellow for the reset command and green for the go command.
Place button code

Call the placeButtons Function

Once the function is built, it must be called from every code that initializes a screen. Here it is called from on start and from moveMe. As explained in the next section, it is also called from each block’s on-broken event.

on start and moveme

Code the on-broken Events

Each block being used as a button must have an on-broken event in which the same code as in the corresponding on-chat command should be run. I like to move the code to a function, which is called from both the on-broken event and the on-chat command. The advantage of putting the code in a function is that if it is modified, it need be changed in only one place.

Each on-broken event must also call placeButtons. Of course, an on-broken event really must replace only the broken button, but the advantage of calling the placeButtons event is that if you want to futz with the location of the buttons, it need be changed only in one place — always a good thing.

all buttons code

Get the Code

Handy Timer with Blocks for Buttons code is shared on Code Connection at this URL

https://makecode.com/_iwCgCd5bsFxY

To get and use the code, follow these steps.

Click the Import button import button , which is upper right in the Code Connection window just below the banner. This will open the window shown below.
Import choices

Click the Import URL button Import URL, which is on the right, to open the window shown below.

Import Copy link

Paste the URL supplied for the program you want to use in the space under the text “Copy the URL …”
import url with url

Click the Go ahead! button go ahead button.

The next window you will see will be the MakeCode window with the code downloaded from the URL. At this point, you can treat it like any other code, e.g., run it, save it locally, modify it, publish your changes or whatever else your heat desires.

We have tested several other methods of downloading the code using the URL, for example, pasting the URL in a browser. No joy. For more detailed instruction see our post How to Use Shared MakeCode on Microsoft Code Connection for Minecraft.

More Grandma’s Chickens 2.0: A Makecode for Minecraft Game

 

Grandma’s Chickens is a game in which the player kills as many chickens as possible racing against the lightning strikes that may kill  chickens  and ocelots that may  eat them before the player can score a kill. Also, lightning might strike the fence making a hole through which chickens can escape.

A cowardly (or impatient) player will choose to use the sword, which is provided in the player inventory. In this case, chickens are killed with a single strike and the fence and ground will not be destroyed accidently. A more difficult version is to use the hand rather than the sword. In this case, it takes a few strikes to kill each chicken and it is frustratingly easy to accidently make holes in the fence or ground. During all this action, the score is updated in the sky. The game can be varied using the on-chat arguments for the size of the fence, the number of chickens and the number of ocelots.

Field GrandmasChickens

Strategy for the Design of the Grandma’s Chickens Game

The strategy for building Grandma’s Chickens was to spawn chickens and ocelots at random positions inside a wooden fence with the player at the center. The player can start killing chickens while they are being  spawned. The on-chicken-killed event keeps score and every few kills randomly spawns a lightning bolt at a random position inside and including the fence. If lightning strikes the fence, a hole is burned in the fence through which chickens can escape. When a chicken is killed, the score is updated by the on-chicken-killed event and printed in the sky.

The Code for Grandma’s Chickens

The key code is the on-chat command “run” and the on-chicken-killed event.

The steps for then on-chat command “run” and described in the following paragraphs.

Step 1: Set the global variable origin, which will be where the west-north corner of the fence is positioned.

Step 2: Store the arguments in global variables– nBLocksPerFenceSide, nChickens and nOcelots. Check the variables for allowed values, switching to defaults if needed. Say these values before and after the validity checks to be sure there is not a problem, like the one described in a MakeCode for Minecraft on Chat Command Arguments Problem (Bug?). Notice that if no arguments are given — “run” — the values are all zero and the defaults are used.

GrandmasChickes Code 1
Grandma’s Chickens Part 1 of 4

Step 3: Calculate fence parameters including the west-north corner (same as origin), the opposing east-south corner  and the center. If the argument for the number of blocks per side is even, increase it d by 1 so that it is odd. This enables an exact center block for the fence; that is, the center block has the exact same number of blocks on the left, right, in front and behind. Yes, I realize that this is being a bit too meticulous. It’s a programmer thing.

GrandmasChickes Code 2

Grandma’s Chickens Run —  Part 2 of 4

Step 4: Move the player to just outside the fence so she will not be in the way. Yes, I know that this is probably not necessary.

Step 5: Build the fence according to the previously calculated parameters.

Step 6: Call the function makeEastPointerFromOrigin, which helps the programmer visualize the fence construction.

Step 7: Give the player a sword to provide the option of striking chickens with a more powerful weapon than just the hand. Using a sword makes the game easier to play, but personally, I prefer the more difficult version using the hand.

Step 8: Initialize the score to zero and print it in the sky.

GrandmasChickes Code 3

Grandma’s Chickens Run —  Part 3 of 4

Step 9: Set the boundaries for spawning chickens and ocelots one block inside the fence. Spawn the number of chickens and ocelots specified by the global variables nChickens and nOcelots, which were set to the values passed in the on-chat arguments or to the default values if on-chat had no arguments or were invalid values.

GrandmasChickes Code 4

Grandma’s Chickens Run —  Part 4 of 4

Grandmas chickens on start On start initializes the values for the global variables. Here it was automatically generated by MakeCode as JavaScript statements. 

An essential part of the Grandma’s Chickens game is the on-animal-chicken-killed event, which  is run when a chicken is killed by the player. Each time the event is triggered, 1 is added to the score and the score is printed in the sky. A random number is picked from the sequence 0, 1, 2. If the random number is 1, a lightning -bolt projectile is spawned at or inside the fence. The number 1 is arbitrary and could have been any of the three number 0, 1 or 2. It simply enables a 1 in 3 chance of the lightning striking.  If the lightning hits the fence, it burns a hole in the fence through which chickens and ocelots can escape. The lightning also sets fire to the grass, which can be annoying when one is in a panic to kill chickens.

Grandmas Chickens kill
grandmas chickens giveswords

The function giveMeSwords first clears the player’s inventory and then gives the player a sword that can be used to kill chickens more efficiently than just the hand. A function was chosen to implement this code rather than coding it inline, so that other items could be easily added to the player inventory to experiment with the game without cluttering the main code. For example, I have considered providing fence blocks so that the player can repair the fence.

Don’t Worry About the Chickens

I know you might be concerned about all those chickens being killed. Don’t be. They were born to be eaten by the hungry folks in the Minecraft world. On the humble farm where I grew up, chickens were feast food. I can still remember the anticipation of a festive meal when my mother was in the yard plucking the chicken feathers from a fine bird that my father had just killed.

Of course, We Are Working on Grandma’s Chickens 3.0

We have lots of ideas for making Grandma’s Chickens even more interesting and fun. We hope you have some, too. We would very much like for you to build on our code.

Get the Code

Grandma’s Chickens 2.0  code is shared on Code Connection at this URL

 https://makecode.com/_RFUKHraM7Tbp

To get and use the code, follow these steps.

Click the Import button import button , which is upper right in the Code Connection window just below the banner. This will open the window shown below.
Import choices

Click the Import URL button Import URL, which is on the right, to open the window shown below.

Import Copy link

Paste the URL supplied for the program you want to use in the space under the text “Copy the URL …”
import url with url

Click the Go ahead! button go ahead button.

The next window you will see will be the MakeCode window with the code downloaded from the URL. At this point, you can treat it like any other code, e.g., run it, save it locally, modify it, publish your changes or whatever else your heat desires.

We have tested several other methods of downloading the code using the URL, for example, pasting the URL in a browser. No joy. For more detailed instruction see our post How to Use Shared MakeCode on Microsoft Code Connection for Minecraft.

Bang! — Simulating an On-TNT-Exploded Event in MakeCode for Minecraft

 

Bang Code

The Bang program  places TNT in the ground of a flat world. It then places a  flint and steel item in the player inventory. The player is teleported to within a few blocks above the TNT so that the TNT can be ignited. 

I wanted the player to be way high above the TNT area so that the full effect of the explosion could be seen. After igniting the TNT, it is hard to manually fly the player rapidly enough and high enough to catch the full view. What I needed was a TNT-Exploded event that, when triggered, would teleport the player high enough to get the desired view. But after reading, searching and experimenting, I didn’t find a way to do this with MakeCode’s built-in events (e.g., on block destroyed).

My solution was to simulate a TNT-Exploded event. The key idea was that after the event is enabled, it repeatedly tests the block under origin. The block is originally grass,  then replaced by TNT, and  when the TNT explodes, it is destroyed and replaced by air. When the event is enabled and the test for air succeeds, the TNT has exploded and the player is teleported high in the sky.

Before running bang, be sure the player is flying; otherwise, she will fall all the way to  bedrock after the teleport. I would like to find a way to programmatically put the player in flying mode, but haven’t found it as of this writing.

The implementation of the TNT-Exploded event uses the global variable TNT_eventEnabled, which is false until the TNT is in place and the player is in position to ignite it. Once the event is enabled, the forever loop, which runs repeatedly, proceeds to test for air under origin. When air is found, the player is teleported sky high and the event is disabled so that it will run only once for each run of bang.

Event

Bang is a companion program to Flat Fixer. Using the two programs, Bang can make a mess and Flat Fixer can clean it up again and again and …

Get the Code

Bang! code is shared on Code Connection at this URL

https://makecode.com/_LC4dzUPe4bYg

To get and use the code, follow these steps.

Click the Import button import button , which is upper right in the Code Connection window just below the banner. This will open the window shown below.
Import choices

Click the Import URL button Import URL, which is on the right, to open the window shown below.

Import Copy link

Paste the URL supplied for the program you want to use in the space under the text “Copy the URL …”
import url with url

Click the Go ahead! button go ahead button.

The next window you will see will be the MakeCode window with the code downloaded from the URL. At this point, you can treat it like any other code, e.g., run it, save it locally, modify it, publish your changes or whatever else your heat desires.

We have tested several other methods of downloading the code using the URL, for example, pasting the URL in a browser. No joy. For more detailed instruction see our post How to Use Shared MakeCode on Microsoft Code Connection for Minecraft.