How to draw image based on values in array

Question

I have an array of terrain types that are represented by numbers (0 = water, 1 = land, etc.)
I need each terrain type to show as a different coloured pixel.
I am currently using an ImageTexture but the createfromimage function is too slow as I want to update the image constantly. I have heard that maybe I should use a shader?

My current slow method:

extends Sprite

var terrain_image = Image.new()
var terrain_texture = ImageTexture.new()

func create_texture(width, height, terrain_array, depth_array):
    var color

    terrain_image.create(width, height, false, Image.FORMAT_RGBA8)
    terrain_image.lock()

    for y in range(height):
        for x in range(width):
            var current_material = terrain_array[y][x]
            var current_depth = depth_array[y][x]
            if  current_material == 0:
                color = Color.blue  # water
                color = color.darkened(abs(current_depth))
            elif current_material == 1:
                color = Color.yellow  # land
                color = color.darkened(current_depth)
            elif current_material == 2:
                color = Color.green
            else:
                color = Color.pink  # error
            terrain_image.set_pixel(x, y, color)

    terrain_image.unlock()
    terrain_texture.create_from_image(terrain_image, 0)


func draw_terrain(width, height, terrain_array, depth_array):
    create_texture(width, height, terrain_array, depth_array)
    self.texture = terrain_texture

Comments

I ended up using sprites for anything that needed quick updating

Answer 1

Neither shaders nor ImageTextures are very efficient way of storing and updating a world, so in this case I'd just stick to using what Godot provides; the TileMap node. You can either create the TileSet manually or by code if you so whish.

Comments

Modifying a TileMap is still slow, though