1 #ifndef MSP_GL_RENDERER_H_
2 #define MSP_GL_RENDERER_H_
22 A class for supervising the rendering process. While many Renderables (in
23 particular, Objects and Scenes) can by rendered without a Renderer, using one
24 will often be more efficient. This is especially true for ObjectInstances.
26 The Renderer works by deferring GL state changes until something is actually
27 being drawn. This avoids many unnecessary GL calls if consecutive renderables
28 use the same resources.
30 A state stack is provided to help with state scoping. Typically a Renderable
31 will push the current state on entry, set whatever state it requires, render
32 itself, and pop the state when it's done. An RAII helper class is provided for
33 the push/pop operation.
44 Push(Renderer &r): renderer(r) { renderer.push_state(); }
45 ~Push() { renderer.pop_state(); }
51 const Texture *texture;
52 const Texturing *texturing;
53 const Material *material;
54 const Program *shprog;
55 unsigned shdata_count;
56 const WindingTest *winding_test;
61 class MtxStack: public MatrixStack
69 virtual void update();
75 std::vector<State> state_stack;
77 std::vector<const ProgramData *> shdata_stack;
79 const VertexArray *vertex_array;
80 bool vertex_array_changed;
81 const Buffer *element_buffer;
84 Renderer(const Camera *);
87 MatrixStack &matrix_stack() { return mtx_stack; }
89 const Camera *get_camera() const { return camera; }
91 void set_texture(const Texture *);
92 void set_texturing(const Texturing *);
93 void set_material(const Material *);
95 /** Sets the shader program to use. An initial set of data can be set as
96 well, with the same semantics as add_shader_data. */
97 void set_shader_program(const Program *prog, const ProgramData *data = 0);
99 /** Adds another set of data to be use with shader programs. The data is
100 independent of any shader program changes and remains in effect until the
101 Renderer state is popped. */
102 void add_shader_data(const ProgramData &data);
104 void set_vertex_array(const VertexArray *);
105 void set_element_buffer(const Buffer *);
106 void set_winding_test(const WindingTest *);
108 /** Saves the current state so it can be restored later. */
111 /** Restores a previously saved state. Must be matched with an earlier
115 /** Prepares for temporarily bypassing the Renderer by synchronizing the
116 current state with GL. No additional call is necessary to resume using the
120 void draw(const Batch &);