contract.py

import smartpy as sp

class SpectrumColors(sp.Contract):
    def __init__(self):
        self.init(
            # fixed dimensions of the board
            columns = 16,
            rows = 16,
            # limit to the total number of colors possible
            max_colors = 12,
            # the map<nat,nat> for the board display
            display = sp.map(tkey = sp.TNat, tvalue = sp.TNat),
        )

    @sp.entry_point
    def update(self, params):
        # update a cell by index with a new color
        sp.verify(sp.amount == sp.tez(0), "the operation does not need tez transfers")
        color = params.color
        idx = params.index
        sp.verify((idx >= 0) & (idx < self.data.rows * self.data.columns), "index out of range")
        sp.verify((color >= 0) & (color < self.data.max_colors), "color index out of range")
        self.data.display[idx] = color

    @sp.offchain_view(pure = True)
    def get_color(self, idx):
        # a view that gets us the color at the specified index
        sp.set_type(idx, sp.TNat)
        sp.verify((idx >= 0) & (idx < self.data.rows * self.data.columns), "index out of range")
        sp.result(self.data.display.get(idx, 0))

if "templates" not in __name__:
    @sp.add_test(name = "SpectrumColors")
    def test():
        c1 = SpectrumColors()
        scenario = sp.test_scenario()
        scenario.h1("SpectrumColors")
        scenario += c1

        x = 0
        y = 2
        rows = 3
        columns = 4
        index = (x + y * columns)
        c1.update(color = 3, index = index)
        c1.update(color = 2, index = index)
        c1.update(color = 6, index = 1)

        scenario.p("Epoch").show(c1.data.display)
        scenario.p("Epoch").show(c1.get_color(index))

    sp.add_compilation_target("storeValue", SpectrumColors())

@mattdesl noice! Is there an easy way for you to dump out the compiled Michelson source too? Would very much like to compare...

Thanks! It’s deployed on test net so Michelson is visible there:

https://better-call.dev/hangzhou2net/KT1MeQytVramwMXJRyksTemX2B7qF4MJoRSG/code

If you have a testnet funds + dev wallet you can also interact with the contract through the block explorer.

Awesome, thanks! Good to see these side by side! 🙏