Add material command

nicklockwood · nicklockwood · commit af1c89918452 · 2023-11-25T08:50:41.000Z
diff --git a/ShapeScript/Interpreter.swift b/ShapeScript/Interpreter.swift
@@ -977,7 +977,16 @@ extension Statement {
             }
         case let .expression(type):
             let expression = Expression(type: type, range: range)
-            try RuntimeError.wrap(context.addValue(expression.evaluate(in: context)), at: range)
+            do {
+                try context.addValue(expression.evaluate(in: context))
+            } catch let error as RuntimeErrorType {
+                // TODO: generalize this
+                guard case .unusedValue(type: ValueType.material.errorDescription) = error,
+                      case .block = type
+                else {
+                    throw RuntimeError(error, at: range)
+                }
+            }
         case let .define(identifier, definition):
             switch definition.type {
             case let .function(names, _):
@@ -1154,7 +1163,7 @@ extension Expression {
                 guard let value = value.as(.list(.path)) ?? value.as(.list(.mesh)),
                       case let .tuple(values) = value
                 else {
-                    fallthrough
+                    throw RuntimeError(.unexpectedArgument(for: name, max: 0), at: block.range)
                 }
                 let sourceIndex = context.sourceIndex
                 let newContext = context.push(.init(.transform, [:], .mesh, value.type))
@@ -1171,11 +1180,47 @@ extension Expression {
                 return .tuple(values.map {
                     .mesh(($0.value as! Geometry).transformed(by: newContext.transform))
                 })
-            case .property, .function((.void, _), _):
-                throw RuntimeError(
-                    .unexpectedArgument(for: name, max: 0),
-                    at: block.range
-                )
+            case let .property(type, setter, _):
+                switch type {
+                case .material:
+                    // TODO: generalize this
+                    let blockType = BlockType([:], [
+                        "color": .color,
+                        "opacity": .number,
+                        "texture": .texture,
+                        "metallicity": .colorOrTexture,
+                        "roughness": .colorOrTexture,
+                        "glow": .colorOrTexture,
+                    ], .void, .material)
+                    let newContext = context.push(blockType)
+                    try newContext.pushScope { newContext in
+                        block.statements.gatherDefinitions(in: newContext)
+                        for statement in block.statements {
+                            try statement.evaluate(in: newContext)
+                        }
+                    }
+                    let diffuse = newContext.value(for: "color") ?? newContext.value(for: "texure")
+                    let material = Material(
+                        opacity: newContext.value(for: "opacity")?.doubleValue ?? 1,
+                        diffuse: diffuse?.colorOrTextureValue,
+                        metallicity: newContext.value(for: "metallicity")?.colorOrTextureValue,
+                        roughness: newContext.value(for: "roughness")?.colorOrTextureValue,
+                        glow: newContext.value(for: "glow")?.colorOrTextureValue
+                    )
+                    try RuntimeError.wrap(setter(.material(material), context), at: range)
+                    return .material(material)
+                case .object, .any, .color, .texture, .boolean, .font, .number, .radians,
+                     .halfturns, .vector, .size, .rotation, .string, .text, .path,
+                     .mesh, .polygon, .point, .range, .bounds, .union, .tuple, .list:
+                    break
+                }
+                throw RuntimeError(.typeMismatch(
+                    for: name,
+                    expected: type.errorDescription,
+                    got: "block"
+                ), at: block.range)
+            case .function((.void, _), _):
+                throw RuntimeError(.unexpectedArgument(for: name, max: 0), at: block.range)
             case let .function((type, _), _):
                 throw RuntimeError(.typeMismatch(
                     for: name,
diff --git a/ShapeScript/StandardLibrary.swift b/ShapeScript/StandardLibrary.swift
@@ -114,6 +114,11 @@ extension Dictionary where Key == String, Value == Symbol {
         }, { context in
             .colorOrTexture(context.material.glow ?? .color(.black))
         }),
+        "material": .property(.material, { parameter, context in
+            context.material = parameter.value as? Material ?? .default
+        }, { context in
+            .material(context.material)
+        }),
     ]
 
     static let polygons: Symbols = [
diff --git a/ShapeScriptTests/InterpreterTests.swift b/ShapeScriptTests/InterpreterTests.swift
@@ -1415,6 +1415,44 @@ class InterpreterTests: XCTestCase {
         }
     }
 
+    // MARK: Material
+
+    func testDefaultMaterial() {
+        let program = """
+        print color
+        print material.color
+        """
+        let delegate = TestDelegate()
+        XCTAssertNoThrow(try evaluate(parse(program), delegate: delegate))
+        XCTAssertEqual(delegate.log, [Color.white, .white])
+    }
+
+    func testColorMaterial() {
+        let program = """
+        material {
+            color (1 0 0)
+        }
+        print color
+        print material.color
+        """
+        let delegate = TestDelegate()
+        XCTAssertNoThrow(try evaluate(parse(program), delegate: delegate))
+        XCTAssertEqual(delegate.log, [Color.red, .red])
+    }
+
+    func testStoredMaterial() {
+        let program = """
+        define foo material {
+            color (1 0 0)
+        }
+        print color
+        print foo.color
+        """
+        let delegate = TestDelegate()
+        XCTAssertNoThrow(try evaluate(parse(program), delegate: delegate))
+        XCTAssertEqual(delegate.log, [Color.white, .red])
+    }
+
     // MARK: Background
 
     func testSetBackgroundColorWithParens() throws {
diff --git a/docs/ios/commands.md b/docs/ios/commands.md
@@ -55,7 +55,7 @@ The `smoothing` command can be used anywhere in the ShapeScript file to override
 
 ## Materials
 
-The `color`, `texture` and `opacity` commands are used to specify the appearance of shapes when rendered. These commands are documented in the [materials](materials.md) section.
+The `material` command (along with individual material property commands such as `color` and `texture`) are used to specify the appearance of shapes when rendered. These commands are documented in the [materials](materials.md) section.
 
 ## Font
 
diff --git a/docs/mac/commands.md b/docs/mac/commands.md
@@ -55,7 +55,7 @@ The `smoothing` command can be used anywhere in the ShapeScript file to override
 
 ## Materials
 
-The `color`, `texture` and `opacity` commands are used to specify the appearance of shapes when rendered. These commands are documented in the [materials](materials.md) section.
+The `material` command (along with individual material property commands such as `color` and `texture`) are used to specify the appearance of shapes when rendered. These commands are documented in the [materials](materials.md) section.
 
 ## Font
 
diff --git a/docs/src/commands.md b/docs/src/commands.md
@@ -55,7 +55,7 @@ The `smoothing` command can be used anywhere in the ShapeScript file to override
 
 ## Materials
 
-The `color`, `texture` and `opacity` commands are used to specify the appearance of shapes when rendered. These commands are documented in the [materials](materials.md) section.
+The `material` command (along with individual material property commands such as `color` and `texture`) are used to specify the appearance of shapes when rendered. These commands are documented in the [materials](materials.md) section.
 
 ## Font
 
