The Bloq grammar is a Antlr4 grammar that is designed to simplify the process of 2D map design for platformer/RPG/maze games. Bloq allows the user to create patterns of different blocks and place them on a canvas without having to learn how to use a game engine.

• Variables
• Conditionals
• Functions
• Loops
• 2D bitmap

Creating a canvas with width w, and height h:

canvas: w, h

Defaults:

w: 100   
h: 100

Placing a block of type at the location (x, y) with shape bitmap:

 block: type 
 start: x, y
 shape: bitmap

Defaults:

start: 0, 0  
shape: 1;

type is a predefined type of block.

Supported blocktypes:

land
water
lava
enemy

bitmap can be a variable that is previously assigned a bitmap, or it can be define on the next line after Shape.
The bitmap should be in the monochrome format, setting a bit to 1 will place a block at that location.
Every row (including the last) must be terminated with semicolon.
The top left bit will be aligned to the start location.
If a block is placed at a location that's already occupied, the new block will replace the old block.

Bitmap Structure:

slantedLine: 
0001;
0010;
0100;
1000;

Placing a slantedline water block at 0, 0 on a 4x4 canvas will look like the following:

canvas: 4, 4

block: water
start: 0, 0
shape:
0001;
0010;
0100;
1000;

You can also place multiple block types in a single statement. The placement of each type of block can be defined in shape. The number associated with each block type corresponds to the position of that block type in the block statement, starting with 1.

canvas: 4, 4

block: water, lava, enemy
start: 0, 0
shape:
0001;
0020;
0300;
1000;

The code above will product the following image:

Bloq supports the following types of variable assignments:

Creating a integer variable named name with value value:

name: value

Creating a bitmap variable named name:

name:
row1;
row2;
...;

Repeating a statement n times:

for i: 1 to 10 {
    statement
}

Statement can be either a variable assignment, a block placement, function call, if-else statement or another loop.

Executes a statement(s) if condition is true, can also have else for when the condition is false (optional):

if (condition) {
    statement
} else {
    statement
}

Condition is a comparison between two mathematical expressions. You can also link conditions using the logic operators (&&, ||). You can also negate a condition with !condition.

Supported comparisons:

Supported operations for mathematical expressions:

Logic operators:

Creating a new function called name with parameters a, b:

define name(a, b) {
    statement
}

Calling the same function with arguments 1 and 2:

call name(1, 2)

canvas: 10, 5

pattern:
21;
12;
21;
12;
21;

for i: 0 to 9 {
    if (i % 2 == 0) {
        block: water, lava
        start: i, 0
        shape: pattern
    }
}

Charlie Li, Janie Wang, Jessica Zhan, John Pham, and Shawn Lu.