glsl_type: Add method to get number of slots used by a type

2 files changed, 37 insertions, 0 deletions

diff --git a/glsl_types.cpp b/glsl_types.cpp
index 290756d..2b7c5bc 100644
--- a/glsl_types.cpp
+++ b/glsl_types.cpp
@@ -732,3 +732,31 @@ glsl_type::field_index(const char *name) const
 
    return -1;
 }
+
+
+unsigned
+glsl_type::component_slots() const
+{
+   switch (this->base_type) {
+   case GLSL_TYPE_UINT:
+   case GLSL_TYPE_INT:
+   case GLSL_TYPE_FLOAT:
+   case GLSL_TYPE_BOOL:
+      return this->components();
+
+   case GLSL_TYPE_STRUCT: {
+      unsigned size = 0;
+
+      for (unsigned i = 0; i < this->length; i++)
+	 size += this->fields.structure[i].type->component_slots();
+
+      return size;
+   }
+
+   case GLSL_TYPE_ARRAY:
+      return this->length * this->fields.array->component_slots();
+
+   default:
+      return 0;
+   }
+}
diff --git a/glsl_types.h b/glsl_types.h
index 3265016..939c173 100644
--- a/glsl_types.h
+++ b/glsl_types.h
@@ -215,6 +215,15 @@ struct glsl_type {
    }
 
    /**
+    * Calculate the number of components slots required to hold this type
+    *
+    * This is used to determine how many uniform or varying locations a type
+    * might occupy.
+    */
+   unsigned component_slots() const;
+
+
+   /**
     * Query whether or not a type is a scalar (non-vector and non-matrix).
     */
    bool is_scalar() const