Improve formatting of an empty loop body

[libs/gl.git] / source / renderable.h

diff --git a/source/renderable.h b/source/renderable.h
index aeee1666dc34f54ba441da0793607d786ea1cb28..6e1505ca5a728c0ac1b012eb797cf00c84321ff4 100644 (file)
--- a/source/renderable.h
+++ b/source/renderable.h
@@ -1,26 +1,60 @@
-/* $Id$
-
-This file is part of libmspgl
-Copyright © 2007  Mikko Rasa, Mikkosoft Productions
-Distributed under the LGPL
-*/
-
 #ifndef MSP_GL_RENDERABLE_H_
 #define MSP_GL_RENDERABLE_H_
 
 #include <string>
+#include <msp/geometry/boundingsphere.h>
 #include "tag.h"
 
 namespace Msp {
 namespace GL {
 
+class Matrix;
+class Renderer;
+
+/**
+Base class for renderable objects.  Rendering is performed with the help of a
+Renderer object.
+
+The render method takes a Tag to identify a render pass.  It can be used with
+a Technique to select alternative rendering methods, such as simplified shaders
+for a depth-only shadow pass.
+
+The setup_frame and finish_frame methods provide a mechanism for performing
+once-per-frame operations.  This is most useful for effects, which may need to
+do auxiliary rendering.  With complex rendering hierarchies, these methods may
+be called multiple times for one frame, but it's guaranteed that no rendering
+will occur before a setup_frame call or after a finish_frame call.
+*/
 class Renderable
 {
+protected:
+       Renderable() { }
 public:
-       virtual int get_order() const { return 0; }
-       virtual bool has_pass(const Tag &tag) const =0;
+       virtual ~Renderable() { }
+
+       /** Returns a key used for grouping Renderables in an InstanceScene.  The
+       returned value is treated as opaque. */
+       virtual long get_instance_key() const { return 0; }
+
+       /** Returns the model matrix of the Renderable.  Null is returned if no such
+       matrix exists.  The matrix should be in world space for some effects to work
+       correctly. */
+       virtual const Matrix *get_matrix() const { return 0; }
+
+       /** Returns a bounding sphere that completely encloses the Renderable.  The
+       bounding sphere is expressed in the renderable's coordinates.  Null is
+       returned if the bounding sphere cannot be determined. */
+       virtual const Geometry::BoundingSphere<float, 3> *get_bounding_sphere() const { return 0; }
+
+       /** Called when starting to render a new frame. */
+       virtual void setup_frame(Renderer &) { }
+
+       /** Called when a complete frame has been rendered. */
+       virtual void finish_frame() { }
 
-       virtual void render(const Tag &tag=Tag()) const =0;
+       /** Renders the Renderable.  Implementors should take care to return the
+       renderer to the state it was in, for example by using Renderer::Push. */
+       virtual void render(Renderer &, const Tag & = Tag()) const = 0;
 };
 
 } // namespace Msp