shaderir: Add parsing expr and stmt

internal/shaderir/glsl.go

@@ -119,5 +119,53 @@ func (p *Program) glslBlock(b *Block, f *Func, level int) []string {
 		lines = append(lines, fmt.Sprintf("%s%s;", idt, p.glslVarDecl(&t, fmt.Sprintf("l%d", idx))))
 		idx++
 	}
+
+	var glslExpr func(e *Expr) string
+	glslExpr = func(e *Expr) string {
+		switch e.Type {
+		case Literal:
+			return e.Value
+		case Ident:
+			return e.Value
+		case Unary:
+			return fmt.Sprintf("%s(%s)", e.Op, glslExpr(&e.Exprs[0]))
+		case Binary:
+			return fmt.Sprintf("(%s) %s (%s)", glslExpr(&e.Exprs[0]), e.Op, glslExpr(&e.Exprs[1]))
+		case Call:
+			return fmt.Sprintf("(%s).(%s)", glslExpr(&e.Exprs[0]), glslExpr(&e.Exprs[1]))
+		case Selector:
+			return fmt.Sprintf("(%s).%s", glslExpr(&e.Exprs[0]), glslExpr(&e.Exprs[1]))
+		case Index:
+			return fmt.Sprintf("(%s)[%s]", glslExpr(&e.Exprs[0]), glslExpr(&e.Exprs[1]))
+		default:
+			return fmt.Sprintf("?(unexpected expr: %d)", e.Type)
+		}
+	}
+
+	for _, s := range b.Stmts {
+		switch s.Type {
+		case ExprStmt:
+			panic("not implemented")
+		case BlockStmt:
+			lines = append(lines, idt+"{")
+			lines = append(lines, p.glslBlock(s.Block, f, level+1)...)
+			lines = append(lines, idt+"}")
+		case Assign:
+			lines = append(lines, fmt.Sprintf("%s%s = %s;", idt, glslExpr(&s.Exprs[0]), glslExpr(&s.Exprs[1])))
+		case If:
+			panic("not implemented")
+		case For:
+			panic("not implemented")
+		case Continue:
+			lines = append(lines, idt+"continue;")
+		case Break:
+			lines = append(lines, idt+"break;")
+		case Discard:
+			lines = append(lines, idt+"discard;")
+		default:
+			lines = append(lines, fmt.Sprintf("%s?(unexpected stmt: %d)", idt, s.Type))
+		}
+	}
+
 	return lines
 }

internal/shaderir/ir_test.go

@@ -151,6 +151,53 @@ varying vec3 V0;`,
 			Glsl: `void F0(in float l0, inout float l1, out float l2) {
 	mat4 l3;
 	mat4 l4;
+}`,
+		},
+		{
+			Name: "FuncAdd",
+			Program: Program{
+				Funcs: []Func{
+					{
+						Name: "F0",
+						InParams: []Type{
+							{Main: Float},
+							{Main: Float},
+						},
+						OutParams: []Type{
+							{Main: Float},
+						},
+						Block: Block{
+							Stmts: []Stmt{
+								{
+									Type: Assign,
+									Exprs: []Expr{
+										{
+											Type:  Ident,
+											Value: "l2",
+										},
+										{
+											Type: Binary,
+											Op:   Add,
+											Exprs: []Expr{
+												{
+													Type:  Ident,
+													Value: "l0",
+												},
+												{
+													Type:  Ident,
+													Value: "l1",
+												},
+											},
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			Glsl: `void F0(in float l0, in float l1, out float l2) {
+	l2 = (l0) + (l1);
 }`,
 		},
 	}

internal/shaderir/program.go

@@ -48,21 +48,22 @@ type Stmt struct {
 	Type      StmtType
 	Exprs     []Expr
 	Condition Expr
-	ElseStmts []Expr
+	ElseExprs []Expr
 	ForInit   Expr
 	ForRest   Expr
+	Block     *Block
 }
 
 type StmtType int
 
 const (
 	ExprStmt StmtType = iota
+	BlockStmt
 	Assign
 	If
 	For
 	Continue
 	Break
-	Return
 	Discard
 )
 
@@ -78,7 +79,6 @@ type ExprType int
 const (
 	Literal ExprType = iota
 	Ident
-	LocalVarID
 	Unary
 	Binary
 	Call