Add r,g,b and x,y,z accessors to triple types.

Author: marsupial

CMakeLists.txt

@@ -291,6 +291,7 @@ TESTSUITE ( and-or-not-synonyms aastep arithmetic array array-derivs array-range
             struct-isomorphic-overload struct-layers
             struct-operator-overload struct-return struct-with-array
             struct-nested struct-nested-assign struct-nested-deep
+            swizzle
             ternary
             testshade-expr
             texture-alpha texture-blur texture-connected-options

src/liboslcomp/ast.cpp

@@ -719,11 +719,37 @@ ASTstructselect::print (std::ostream &out, int indentlevel) const
 
 
 
-ASTfieldselect* ASTfieldselect::create (OSLCompilerImpl *comp, ASTNode *expr,
-                                        ustring field) {
+ASTNode* ASTfieldselect::create (OSLCompilerImpl *comp, ASTNode *expr,
+                                 ustring field)
+{
     if (expr->typespec().is_structure_based())
         return new ASTstructselect (comp, expr, field);
 
+    const TypeSpec &type = expr->nodetype() != structselect_node ? expr->typespec() :
+                           static_cast<ASTstructselect*>(expr)->fieldsym()->typespec();
+
+    if (type.aggregate() == TypeDesc::VEC3) {
+        int component = -1;
+        switch (field[0]) {
+            case 'r': component = 0; break;
+            case 'g': component = 1; break;
+            case 'b': component = 2; break;
+
+            case 'x': component = 0; break;
+            case 'y': component = 1; break;
+            case 'z': component = 2; break;
+
+            default:  break;
+        }
+        if (component != -1) {
+            if (expr->nodetype() == index_node) {
+                static_cast<ASTindex*>(expr)->extend(new ASTliteral (comp, component));
+                return expr;
+            }
+            return new ASTindex (comp, expr, new ASTliteral (comp, component));
+        }
+    }
+
     comp->error (comp->filename(), comp->lineno(),
                  "type '%s' does not have a member '%s'",
                  comp->type_c_str(expr->typespec()), field);

src/liboslcomp/ast.h

@@ -579,6 +579,13 @@ class ASTindex : public ASTNode
                                             ustring destname, ustring srcname,
                                             Symbol *index);
 
+    /// Add another index: obj[current][extended]
+    ///
+    void extend (ASTNode *ext) {
+        ASSERT (nchildren() < 4);
+        m_children.emplace_back(ext);
+    }
+
     ref lvalue () const { return child (0); }
     ref index () const { return child (1); }
     ref index2 () const { return child (2); }
@@ -598,8 +605,7 @@ class ASTfieldselect : public ASTNode
     ustring m_fullname;       ///< Full name of variable and field
 
 public:
-    static ASTfieldselect* create (OSLCompilerImpl *comp, ASTNode *expr,
-                                   ustring field);
+    static ASTNode* create (OSLCompilerImpl *comp, ASTNode *expr, ustring field);
 
     ustring field () const { return m_field; }
     ustring fullname () const { return m_fullname; }

testsuite/swizzle/ref/out.txt

@@ -0,0 +1,15 @@
+Compiled swizzle.osl -> swizzle.oso
+c.r: 4
+c.g: 3
+c.b: 2
+v0.x: 6
+v0.y: 7
+v0.z: 8
+v0.z->x: 6
+c4[0].r: 1
+c4[0].g: 2
+c4[0].b: 3
+c4[1].r: -1
+c4[1].b: -3
+c4[1].g: -2
+

testsuite/swizzle/run.py

@@ -0,0 +1,4 @@
+#!/usr/bin/env python
+
+command = testshade("swizzle")
+

testsuite/swizzle/swizzle.osl

@@ -0,0 +1,29 @@
+// Test swizzle statements
+
+#include "color4.h"
+
+shader swizzle ()
+{
+    color c = color(4,3,2);
+    printf("c.r: %g\n", c.r);
+    printf("c.g: %g\n", c.g);
+    printf("c.b: %g\n", c.b);
+
+    vector v0 = vector(6,7,8);
+    printf("v0.x: %g\n", v0.x);
+    printf("v0.y: %g\n", v0.y);
+    printf("v0.z: %g\n", v0.z);
+    v0.z = v0.x;
+    printf("v0.z->x: %g\n", v0.r);
+
+    color  ca[2] = { color(-1,2,3), color(1,-2,-3) };
+    color4 c4[2]; // FIXME: = { color4(color(1,2,3),4), color4(color(-1,-2,-3),-4) };
+
+    for (int i = 0; i < 2; ++i) {
+        ca[i].r = -ca[i].r;
+        c4[i].rgb = color(ca[i].x, ca[i].y, ca[i].z);
+        printf("c4[%d].r: %g\n", i, c4[i].rgb.r);
+        printf("c4[%d].%s: %g\n", i, i ? "b" : "g", i ? c4[i].rgb.b : c4[i].rgb.g);
+        printf("c4[%d].%s: %g\n", i, i ? "g" : "b", i ? c4[i].rgb.g : c4[i].rgb.b);
+    }
+}