Preliminary support for global_settings.

7 files changed, 177 insertions, 83 deletions

diff --git a/dimension/common.terminals b/dimension/common.terminals
index fbe1eb2..20b6459 100644
--- a/dimension/common.terminals
+++ b/dimension/common.terminals
@@ -90,7 +90,7 @@
 %token DMNSN_T_ASCII
 %token DMNSN_T_ASIN
 %token DMNSN_T_ASINH
-%token DMNSN_T_ASSUMED_GAMMA
+%token DMNSN_T_ASSUMED_GAMMA            "assumed_gamma"
 %token DMNSN_T_ATAN
 %token DMNSN_T_ATAN2
 %token DMNSN_T_ATANH
@@ -211,7 +211,7 @@
 %token DMNSN_T_GATHER
 %token DMNSN_T_GIF
 %token DMNSN_T_GLOBAL_LIGHTS
-%token DMNSN_T_GLOBAL_SETTINGS
+%token DMNSN_T_GLOBAL_SETTINGS          "global_settings"
 %token DMNSN_T_GRADIENT
 %token DMNSN_T_GRANITE
 %token DMNSN_T_GRAY                     "gray"
@@ -277,7 +277,7 @@
 %token DMNSN_T_MAX_ITERATION
 %token DMNSN_T_MAX_SAMPLE
 %token DMNSN_T_MAX_TRACE
-%token DMNSN_T_MAX_TRACE_LEVEL
+%token DMNSN_T_MAX_TRACE_LEVEL          "max_trace_level"
 %token DMNSN_T_MEDIA
 %token DMNSN_T_MEDIA_ATTENUATION
 %token DMNSN_T_MEDIA_INTERACTION
diff --git a/dimension/grammar.epilogue b/dimension/grammar.epilogue
index 6ea459d..d666b0a 100644
--- a/dimension/grammar.epilogue
+++ b/dimension/grammar.epilogue
@@ -116,24 +116,24 @@ dmnsn_astnode_string(dmnsn_astnode_type astnode_type)
 
   dmnsn_astnode_map(DMNSN_AST_NONE, "none");
 
-  dmnsn_astnode_map(DMNSN_AST_ROTATION, "rotate");
-  dmnsn_astnode_map(DMNSN_AST_SCALE, "scale");
-  dmnsn_astnode_map(DMNSN_AST_TRANSLATION, "translate");
-
-  dmnsn_astnode_map(DMNSN_AST_CAMERA, "camera");
-  dmnsn_astnode_map(DMNSN_AST_PERSPECTIVE, "perspective");
-  dmnsn_astnode_map(DMNSN_AST_LOCATION, "location");
-  dmnsn_astnode_map(DMNSN_AST_RIGHT, "right");
-  dmnsn_astnode_map(DMNSN_AST_UP, "up");
-  dmnsn_astnode_map(DMNSN_AST_SKY, "sky");
-  dmnsn_astnode_map(DMNSN_AST_ANGLE, "angle");
-  dmnsn_astnode_map(DMNSN_AST_LOOK_AT, "look_at");
-  dmnsn_astnode_map(DMNSN_AST_DIRECTION, "direction");
+  dmnsn_astnode_map(DMNSN_AST_GLOBAL_SETTINGS, "global_settings");
+  dmnsn_astnode_map(DMNSN_AST_ASSUMED_GAMMA,   "assumed_gamma");
+  dmnsn_astnode_map(DMNSN_AST_MAX_TRACE_LEVEL, "max_trace_level");
 
   dmnsn_astnode_map(DMNSN_AST_BACKGROUND, "background");
 
-  dmnsn_astnode_map(DMNSN_AST_BOX, "box");
-  dmnsn_astnode_map(DMNSN_AST_SPHERE, "sphere");
+  dmnsn_astnode_map(DMNSN_AST_CAMERA,      "camera");
+  dmnsn_astnode_map(DMNSN_AST_PERSPECTIVE, "perspective");
+  dmnsn_astnode_map(DMNSN_AST_LOCATION,    "location");
+  dmnsn_astnode_map(DMNSN_AST_RIGHT,       "right");
+  dmnsn_astnode_map(DMNSN_AST_UP,          "up");
+  dmnsn_astnode_map(DMNSN_AST_SKY,         "sky");
+  dmnsn_astnode_map(DMNSN_AST_ANGLE,       "angle");
+  dmnsn_astnode_map(DMNSN_AST_LOOK_AT,     "look_at");
+  dmnsn_astnode_map(DMNSN_AST_DIRECTION,   "direction");
+
+  dmnsn_astnode_map(DMNSN_AST_BOX,          "box");
+  dmnsn_astnode_map(DMNSN_AST_SPHERE,       "sphere");
   dmnsn_astnode_map(DMNSN_AST_LIGHT_SOURCE, "light_source");
 
   dmnsn_astnode_map(DMNSN_AST_OBJECT_MODIFIERS, "object-modifiers");
@@ -142,18 +142,22 @@ dmnsn_astnode_string(dmnsn_astnode_type astnode_type)
 
   dmnsn_astnode_map(DMNSN_AST_PIGMENT, "pigment");
 
-  dmnsn_astnode_map(DMNSN_AST_FINISH, "finish");
-  dmnsn_astnode_map(DMNSN_AST_AMBIENT, "ambient");
-  dmnsn_astnode_map(DMNSN_AST_DIFFUSE, "diffuse");
-  dmnsn_astnode_map(DMNSN_AST_PHONG, "phong");
+  dmnsn_astnode_map(DMNSN_AST_FINISH,     "finish");
+  dmnsn_astnode_map(DMNSN_AST_AMBIENT,    "ambient");
+  dmnsn_astnode_map(DMNSN_AST_DIFFUSE,    "diffuse");
+  dmnsn_astnode_map(DMNSN_AST_PHONG,      "phong");
   dmnsn_astnode_map(DMNSN_AST_PHONG_SIZE, "phong_size");
 
-  dmnsn_astnode_map(DMNSN_AST_REFLECTION, "reflection");
+  dmnsn_astnode_map(DMNSN_AST_REFLECTION,       "reflection");
   dmnsn_astnode_map(DMNSN_AST_REFLECTION_ITEMS, "reflection-items");
-  dmnsn_astnode_map(DMNSN_AST_FALLOFF, "falloff");
+  dmnsn_astnode_map(DMNSN_AST_FALLOFF,          "falloff");
 
   dmnsn_astnode_map(DMNSN_AST_INTERIOR, "interior");
-  dmnsn_astnode_map(DMNSN_AST_IOR, "ior");
+  dmnsn_astnode_map(DMNSN_AST_IOR,      "ior");
+
+  dmnsn_astnode_map(DMNSN_AST_ROTATION,    "rotate");
+  dmnsn_astnode_map(DMNSN_AST_SCALE,       "scale");
+  dmnsn_astnode_map(DMNSN_AST_TRANSLATION, "translate");
 
   dmnsn_astnode_map(DMNSN_AST_FLOAT, "float");
   dmnsn_astnode_map(DMNSN_AST_INTEGER, "integer");
@@ -174,11 +178,11 @@ dmnsn_astnode_string(dmnsn_astnode_type astnode_type)
   dmnsn_astnode_map(DMNSN_AST_AND,           "&" );
   dmnsn_astnode_map(DMNSN_AST_OR,            "|" );
 
-  dmnsn_astnode_map(DMNSN_AST_NEGATE, "-");
-  dmnsn_astnode_map(DMNSN_AST_DOT_X, ".x");
-  dmnsn_astnode_map(DMNSN_AST_DOT_Y, ".y");
-  dmnsn_astnode_map(DMNSN_AST_DOT_Z, ".z");
-  dmnsn_astnode_map(DMNSN_AST_DOT_T, ".t");
+  dmnsn_astnode_map(DMNSN_AST_NEGATE,       "-");
+  dmnsn_astnode_map(DMNSN_AST_DOT_X,        ".x");
+  dmnsn_astnode_map(DMNSN_AST_DOT_Y,        ".y");
+  dmnsn_astnode_map(DMNSN_AST_DOT_Z,        ".z");
+  dmnsn_astnode_map(DMNSN_AST_DOT_T,        ".t");
   dmnsn_astnode_map(DMNSN_AST_DOT_TRANSMIT, ".transmit");
 
   dmnsn_astnode_map(DMNSN_AST_IDENTIFIER, "identifier");
diff --git a/dimension/grammar.nonterminals b/dimension/grammar.nonterminals
index 5b29089..896bff9 100644
--- a/dimension/grammar.nonterminals
+++ b/dimension/grammar.nonterminals
@@ -22,6 +22,11 @@
 /* Top-level items */
 %type <astnode> SCENE_ITEM
 
+/* Global settings */
+%type <astnode> GLOBAL_SETTINGS
+%type <astnode> GLOBAL_SETTINGS_ITEMS
+%type <astnode> GLOBAL_SETTINGS_ITEM
+
 /* Atmospheric effects */
 %type <astnode> ATMOSPHERIC_EFFECT
 %type <astnode> BACKGROUND
diff --git a/dimension/grammar.rules b/dimension/grammar.rules
index af8a5de..25f8a3c 100644
--- a/dimension/grammar.rules
+++ b/dimension/grammar.rules
@@ -30,11 +30,40 @@ SCENE: /* empty */
 ;
 
 /* Top-level scene item */
-SCENE_ITEM: ATMOSPHERIC_EFFECT
+SCENE_ITEM: GLOBAL_SETTINGS
+          | ATMOSPHERIC_EFFECT
           | CAMERA
           | OBJECT
 ;
 
+/* Global settings */
+
+GLOBAL_SETTINGS: "global_settings" "{"
+                   GLOBAL_SETTINGS_ITEMS
+                 "}"
+               {
+                 $$ = $3;
+               }
+;
+
+GLOBAL_SETTINGS_ITEMS: /* empty */ {
+                       $$ = dmnsn_new_astnode(DMNSN_AST_GLOBAL_SETTINGS, @$);
+                     }
+                     | GLOBAL_SETTINGS_ITEMS GLOBAL_SETTINGS_ITEM {
+                       $$ = $1;
+                       dmnsn_array_push($$.children, &$2);
+                     }
+;
+
+GLOBAL_SETTINGS_ITEM: "assumed_gamma" FLOAT {
+                      $$ = dmnsn_new_astnode1(DMNSN_AST_ASSUMED_GAMMA, @$, $2);
+                    }
+                    | "max_trace_level" FLOAT {
+                      $$ = dmnsn_new_astnode1(DMNSN_AST_MAX_TRACE_LEVEL,
+                                              @$, $2);
+                    }
+;
+
 /* Atmospheric effects */
 
 ATMOSPHERIC_EFFECT: BACKGROUND
diff --git a/dimension/lexer.l b/dimension/lexer.l
index 6531e0c..05c6711 100644
--- a/dimension/lexer.l
+++ b/dimension/lexer.l
@@ -163,50 +163,53 @@ unsigned long wchar;
 }
 
 (?# Keywords)
-"ambient"       RETURN_TOKEN(DMNSN_T_AMBIENT);
-"angle"         RETURN_TOKEN(DMNSN_T_ANGLE);
-"background"    RETURN_TOKEN(DMNSN_T_BACKGROUND);
-"box"           RETURN_TOKEN(DMNSN_T_BOX);
-"blue"          RETURN_TOKEN(DMNSN_T_BLUE);
-"camera"        RETURN_TOKEN(DMNSN_T_CAMERA);
-"color"         RETURN_TOKEN(DMNSN_T_COLOR);
-"colour"        RETURN_TOKEN(DMNSN_T_COLOR);
-"direction"     RETURN_TOKEN(DMNSN_T_DIRECTION);
-"diffuse"       RETURN_TOKEN(DMNSN_T_DIFFUSE);
-"falloff"       RETURN_TOKEN(DMNSN_T_FALLOFF);
-"filter"        RETURN_TOKEN(DMNSN_T_FILTER);
-"finish"        RETURN_TOKEN(DMNSN_T_FINISH);
-"gray"          RETURN_TOKEN(DMNSN_T_GRAY);
-"grey"          RETURN_TOKEN(DMNSN_T_GRAY);
-"green"         RETURN_TOKEN(DMNSN_T_GREEN);
-"interior"      RETURN_TOKEN(DMNSN_T_INTERIOR);
-"ior"           RETURN_TOKEN(DMNSN_T_IOR);
-"location"      RETURN_TOKEN(DMNSN_T_LOCATION);
-"look_at"       RETURN_TOKEN(DMNSN_T_LOOK_AT);
-"light_source"  RETURN_TOKEN(DMNSN_T_LIGHT_SOURCE);
-"perspective"   RETURN_TOKEN(DMNSN_T_PERSPECTIVE);
-"phong"         RETURN_TOKEN(DMNSN_T_PHONG);
-"phong_size"    RETURN_TOKEN(DMNSN_T_PHONG_SIZE);
-"pigment"       RETURN_TOKEN(DMNSN_T_PIGMENT);
-"red"           RETURN_TOKEN(DMNSN_T_RED);
-"reflection"    RETURN_TOKEN(DMNSN_T_REFLECTION);
-"rgb"           RETURN_TOKEN(DMNSN_T_RGB);
-"rgbf"          RETURN_TOKEN(DMNSN_T_RGBF);
-"rgbft"         RETURN_TOKEN(DMNSN_T_RGBFT);
-"rgbt"          RETURN_TOKEN(DMNSN_T_RGBT);
-"right"         RETURN_TOKEN(DMNSN_T_RIGHT);
-"rotate"        RETURN_TOKEN(DMNSN_T_ROTATE);
-"sphere"        RETURN_TOKEN(DMNSN_T_SPHERE);
-"sky"           RETURN_TOKEN(DMNSN_T_SKY);
-"t"             RETURN_TOKEN(DMNSN_T_T);
-"texture"       RETURN_TOKEN(DMNSN_T_TEXTURE);
-"transmit"      RETURN_TOKEN(DMNSN_T_TRANSMIT);
-"u"             RETURN_TOKEN(DMNSN_T_U);
-"up"            RETURN_TOKEN(DMNSN_T_UP);
-"v"             RETURN_TOKEN(DMNSN_T_V);
-"x"             RETURN_TOKEN(DMNSN_T_X);
-"y"             RETURN_TOKEN(DMNSN_T_Y);
-"z"             RETURN_TOKEN(DMNSN_T_Z);
+"ambient"               RETURN_TOKEN(DMNSN_T_AMBIENT);
+"angle"                 RETURN_TOKEN(DMNSN_T_ANGLE);
+"assumed_gamma"         RETURN_TOKEN(DMNSN_T_ASSUMED_GAMMA);
+"background"            RETURN_TOKEN(DMNSN_T_BACKGROUND);
+"box"                   RETURN_TOKEN(DMNSN_T_BOX);
+"blue"                  RETURN_TOKEN(DMNSN_T_BLUE);
+"camera"                RETURN_TOKEN(DMNSN_T_CAMERA);
+"color"                 RETURN_TOKEN(DMNSN_T_COLOR);
+"colour"                RETURN_TOKEN(DMNSN_T_COLOR);
+"direction"             RETURN_TOKEN(DMNSN_T_DIRECTION);
+"diffuse"               RETURN_TOKEN(DMNSN_T_DIFFUSE);
+"falloff"               RETURN_TOKEN(DMNSN_T_FALLOFF);
+"filter"                RETURN_TOKEN(DMNSN_T_FILTER);
+"finish"                RETURN_TOKEN(DMNSN_T_FINISH);
+"global_settings"       RETURN_TOKEN(DMNSN_T_GLOBAL_SETTINGS);
+"gray"                  RETURN_TOKEN(DMNSN_T_GRAY);
+"grey"                  RETURN_TOKEN(DMNSN_T_GRAY);
+"green"                 RETURN_TOKEN(DMNSN_T_GREEN);
+"interior"              RETURN_TOKEN(DMNSN_T_INTERIOR);
+"ior"                   RETURN_TOKEN(DMNSN_T_IOR);
+"location"              RETURN_TOKEN(DMNSN_T_LOCATION);
+"look_at"               RETURN_TOKEN(DMNSN_T_LOOK_AT);
+"light_source"          RETURN_TOKEN(DMNSN_T_LIGHT_SOURCE);
+"max_trace_level"       RETURN_TOKEN(DMNSN_T_MAX_TRACE_LEVEL);
+"perspective"           RETURN_TOKEN(DMNSN_T_PERSPECTIVE);
+"phong"                 RETURN_TOKEN(DMNSN_T_PHONG);
+"phong_size"            RETURN_TOKEN(DMNSN_T_PHONG_SIZE);
+"pigment"               RETURN_TOKEN(DMNSN_T_PIGMENT);
+"red"                   RETURN_TOKEN(DMNSN_T_RED);
+"reflection"            RETURN_TOKEN(DMNSN_T_REFLECTION);
+"rgb"                   RETURN_TOKEN(DMNSN_T_RGB);
+"rgbf"                  RETURN_TOKEN(DMNSN_T_RGBF);
+"rgbft"                 RETURN_TOKEN(DMNSN_T_RGBFT);
+"rgbt"                  RETURN_TOKEN(DMNSN_T_RGBT);
+"right"                 RETURN_TOKEN(DMNSN_T_RIGHT);
+"rotate"                RETURN_TOKEN(DMNSN_T_ROTATE);
+"sphere"                RETURN_TOKEN(DMNSN_T_SPHERE);
+"sky"                   RETURN_TOKEN(DMNSN_T_SKY);
+"t"                     RETURN_TOKEN(DMNSN_T_T);
+"texture"               RETURN_TOKEN(DMNSN_T_TEXTURE);
+"transmit"              RETURN_TOKEN(DMNSN_T_TRANSMIT);
+"u"                     RETURN_TOKEN(DMNSN_T_U);
+"up"                    RETURN_TOKEN(DMNSN_T_UP);
+"v"                     RETURN_TOKEN(DMNSN_T_V);
+"x"                     RETURN_TOKEN(DMNSN_T_X);
+"y"                     RETURN_TOKEN(DMNSN_T_Y);
+"z"                     RETURN_TOKEN(DMNSN_T_Z);
 
 (?# Directives)
 #[\b\r\t\v ]*break              RETURN_TOKEN(DMNSN_T_BREAK);
diff --git a/dimension/parse.h b/dimension/parse.h
index 2d946b6..6da36d7 100644
--- a/dimension/parse.h
+++ b/dimension/parse.h
@@ -30,9 +30,11 @@
 typedef enum {
   DMNSN_AST_NONE,
 
-  DMNSN_AST_ROTATION,
-  DMNSN_AST_SCALE,
-  DMNSN_AST_TRANSLATION,
+  DMNSN_AST_GLOBAL_SETTINGS,
+  DMNSN_AST_ASSUMED_GAMMA,
+  DMNSN_AST_MAX_TRACE_LEVEL,
+
+  DMNSN_AST_BACKGROUND,
 
   DMNSN_AST_CAMERA,
   DMNSN_AST_PERSPECTIVE,
@@ -44,8 +46,6 @@ typedef enum {
   DMNSN_AST_LOOK_AT,
   DMNSN_AST_DIRECTION,
 
-  DMNSN_AST_BACKGROUND,
-
   DMNSN_AST_BOX,
   DMNSN_AST_LIGHT_SOURCE,
   DMNSN_AST_SPHERE,
@@ -69,6 +69,10 @@ typedef enum {
   DMNSN_AST_INTERIOR,
   DMNSN_AST_IOR,
 
+  DMNSN_AST_ROTATION,
+  DMNSN_AST_SCALE,
+  DMNSN_AST_TRANSLATION,
+
   DMNSN_AST_FLOAT,
   DMNSN_AST_INTEGER,
 
diff --git a/dimension/realize.c b/dimension/realize.c
index c41ac93..9fa333b 100644
--- a/dimension/realize.c
+++ b/dimension/realize.c
@@ -24,6 +24,23 @@
 #include <stdio.h>
 #include <stdbool.h>
 
+static long
+dmnsn_realize_integer(dmnsn_astnode astnode)
+{
+  switch (astnode.type) {
+  case DMNSN_AST_INTEGER:
+    return *(long *)astnode.ptr;
+  case DMNSN_AST_FLOAT:
+    dmnsn_diagnostic(astnode.filename, astnode.line, astnode.col,
+                     "WARNING: float cast to integer");
+    return *(double *)astnode.ptr;
+
+  default:
+    dmnsn_assert(false, "Invalid integer.");
+    return 0; /* Silence compiler warning */
+  }
+}
+
 static double
 dmnsn_realize_float(dmnsn_astnode astnode)
 {
@@ -137,6 +154,34 @@ dmnsn_realize_translation(dmnsn_astnode astnode)
   return dmnsn_translation_matrix(trans);
 }
 
+static void
+dmnsn_realize_global_settings(dmnsn_astnode astnode, dmnsn_scene *scene)
+{
+  dmnsn_assert(astnode.type == DMNSN_AST_GLOBAL_SETTINGS,
+               "Expected global settings.");
+
+  unsigned int i;
+  for (i = 0; i < dmnsn_array_size(astnode.children); ++i) {
+    dmnsn_astnode item, child;
+    dmnsn_array_get(astnode.children, i, &item);
+
+    switch (item.type) {
+    case DMNSN_AST_ASSUMED_GAMMA:
+      dmnsn_diagnostic(item.filename, item.line, item.col,
+                       "WARNING: assumed_gamma not supported");
+      break;
+
+    case DMNSN_AST_MAX_TRACE_LEVEL:
+      dmnsn_array_get(item.children, 0, &child);
+      scene->reclimit = dmnsn_realize_integer(child);
+      break;
+
+    default:
+      dmnsn_assert(false, "Invalid global settings item.");
+    }
+  }
+}
+
 static dmnsn_camera *
 dmnsn_realize_camera(dmnsn_astnode astnode)
 {
@@ -741,9 +786,8 @@ dmnsn_realize_astree(const dmnsn_astree *astree)
     dmnsn_light  *light;
     dmnsn_object *object;
     switch (astnode.type) {
-    case DMNSN_AST_CAMERA:
-      dmnsn_delete_camera(scene->camera);
-      scene->camera = dmnsn_realize_camera(astnode);
+    case DMNSN_AST_GLOBAL_SETTINGS:
+      dmnsn_realize_global_settings(astnode, scene);
       break;
 
     case DMNSN_AST_BACKGROUND:
@@ -751,6 +795,11 @@ dmnsn_realize_astree(const dmnsn_astree *astree)
       scene->background = dmnsn_realize_color(astnode);
       break;
 
+    case DMNSN_AST_CAMERA:
+      dmnsn_delete_camera(scene->camera);
+      scene->camera = dmnsn_realize_camera(astnode);
+      break;
+
     case DMNSN_AST_BOX:
       object = dmnsn_realize_box(astnode);
       dmnsn_array_push(scene->objects, &object);