add sand, glass, and calculator (#362)

- Sand is now found near water.  Sand regenerates immediately (like water).
- Sand can be used in a furnace to make glass.
- Glass + copper wires + 3D printer can be used to make solar panels.
    - Note that with #361 I intend to start the base with a small number of 3D printers, so other robots could carry this out.  But also, the base will start with a bunch of solar panels too.
- Solar panel + counter can be used to make a calculator.

data/entities.yaml

@@ -216,6 +216,24 @@
   properties: [portable]
   capabilities: [float]
 
+- name: sand
+  display:
+    attr: sand
+    char: '█'
+  description:
+  - A substance composed mostly of tiny rocks and mineral particles.  It
+    tends to be found near water, and can be used in a furnace to make glass.
+  properties: [portable, growable]
+  growth: [0,0]
+
+- name: glass
+  display:
+    attr: entity
+    char: '□'
+  description:
+  - A pane of a brittle, clear substance, made from melting sand in a furnace.
+  properties: [portable]
+
 - name: bit (0)
   display:
     attr: entity
@@ -378,7 +396,7 @@
 - name: plasma cutter
   display:
     attr: device
-    char: '+'
+    char: 'P'
   description:
   - "A plasma cutter uses a jet of hot plasma to cut through metal like
     butter.  Used via the 'salvage' command to cut apart old robots."
@@ -546,3 +564,14 @@
     uses the 'log' command)."
   properties: [portable]
   capabilities: [log]
+
+- name: calculator
+  display:
+    attr: device
+    char: '+'
+  description:
+  - "A calculator allows a robot to do basic arithmetic calculations:
+    addition, subtraction, multiplication, division, and
+    exponentiation."
+  properties: [portable]
+  capabilities: [arith]

data/recipes.yaml

@@ -108,6 +108,27 @@
   required:
   - [1, furnace]
 
+- in:
+  - [1, sand]
+  out:
+  - [1, glass]
+  required:
+  - [1, furnace]
+
+- in:
+  - [1, glass]
+  - [8, copper wire]
+  out:
+  - [1, solar panel]
+  required:
+  - [1, 3D printer]
+
+- in:
+  - [1, counter]
+  - [1, solar panel]
+  out:
+  - [1, calculator]
+
 - in:
   - [32, gear]
   - [6, copper wire]

src/Swarm/Game/WorldGen.hs

@@ -66,6 +66,7 @@ testWorld2 baseSeed (Coords ix@(r, c)) =
     | h `mod` 10 == 0 = (StoneT, Just "rock")
     | otherwise = (StoneT, Nothing)
   genBiome Big Soft Natural
+    | abs (sample ix pn1) < 0.1 = (DirtT, Just "sand")
     | even (r + c) = (DirtT, Just "wavy water")
     | otherwise = (DirtT, Just "water")
   genBiome Small Soft Natural

src/Swarm/Language/Capability.hs

@@ -266,6 +266,12 @@ constCaps =
     Salvage -> [CSalvage]
     Reprogram -> [CReprogram]
     Drill -> [CDrill]
+    Neg -> [CArith]
+    Add -> [CArith]
+    Sub -> [CArith]
+    Mul -> [CArith]
+    Div -> [CArith]
+    Exp -> [CArith]
     -- Some God-like sensing abilities.
     As -> [CGod]
     RobotNamed -> [CGod]
@@ -278,7 +284,6 @@ constCaps =
     Appear -> [CAppear] -- paint?
     Whereami -> [CSenseloc] -- GPS?
     Random -> [CRandom] -- randomness device (with bitcoins)?
-    Neg -> [CArith] -- ALU? pocket calculator?
     Whoami -> [CWhoami] -- mirror, needs a recipe
 
     -- comparator?
@@ -290,11 +295,6 @@ constCaps =
     Geq -> [CCompare]
     And -> []
     Or -> []
-    Add -> [CArith]
-    Sub -> [CArith]
-    Mul -> [CArith]
-    Div -> [CArith]
-    Exp -> [CArith]
     -- Some more constants which *ought* to have their own capability but
     -- currently don't.
     Say -> []