1 #ifndef _EFFECT_CHAIN_H
2 #define _EFFECT_CHAIN_H 1
8 #include "image_format.h"
14 // A node in the graph; basically an effect and some associated information.
20 // Edges in the graph (forward and backward).
21 std::vector<Node *> outgoing_links;
22 std::vector<Node *> incoming_links;
25 // Identifier used to create unique variables in GLSL.
26 std::string effect_id;
28 // Logical size of the output of this effect, ie. the resolution
29 // you would get if you sampled it as a texture. If it is undefined
30 // (since the inputs differ in resolution), it will be 0x0.
31 // If both this and output_texture_{width,height} are set,
32 // they will be equal.
33 unsigned output_width, output_height;
35 // If output goes to RTT (otherwise, none of these are set).
36 // The Phase pointer is a but ugly; we should probably fix so
37 // that Phase takes other phases as inputs, instead of Node.
38 GLuint output_texture;
39 unsigned output_texture_width, output_texture_height;
42 // Used during the building of the effect chain.
43 ColorSpace output_color_space;
44 GammaCurve output_gamma_curve;
46 friend class EffectChain;
49 // A rendering phase; a single GLSL program rendering a single quad.
51 GLint glsl_program_num;
52 bool input_needs_mipmaps;
54 // Inputs are only inputs from other phases (ie., those that come from RTT);
55 // input textures are not counted here.
56 std::vector<Node *> inputs;
58 std::vector<Node *> effects; // In order.
59 unsigned output_width, output_height;
64 EffectChain(float aspect_nom, float aspect_denom); // E.g., 16.0f, 9.0f for 16:9.
67 // input, effects, output, finalize need to come in that specific order.
69 // EffectChain takes ownership of the given input.
70 // input is returned back for convenience.
71 Input *add_input(Input *input);
73 // EffectChain takes ownership of the given effect.
74 // effect is returned back for convenience.
75 Effect *add_effect(Effect *effect) {
76 return add_effect(effect, last_added_effect());
78 Effect *add_effect(Effect *effect, Effect *input) {
79 std::vector<Effect *> inputs;
80 inputs.push_back(input);
81 return add_effect(effect, inputs);
83 Effect *add_effect(Effect *effect, Effect *input1, Effect *input2) {
84 std::vector<Effect *> inputs;
85 inputs.push_back(input1);
86 inputs.push_back(input2);
87 return add_effect(effect, inputs);
89 Effect *add_effect(Effect *effect, const std::vector<Effect *> &inputs);
91 void add_output(const ImageFormat &format);
94 //void render(unsigned char *src, unsigned char *dst);
95 void render_to_screen()
97 render_to_fbo(0, 0, 0);
100 // Render the effect chain to the given FBO. If width=height=0, keeps
101 // the current viewport.
102 void render_to_fbo(GLuint fbo, unsigned width, unsigned height);
104 Effect *last_added_effect() {
108 return nodes.back()->effect;
112 // API for manipulating the graph directly. Intended to be used from
113 // effects and by EffectChain itself.
115 // Note that for nodes with multiple inputs, the order of calls to
116 // connect_nodes() will matter.
117 Node *add_node(Effect *effect);
118 void connect_nodes(Node *sender, Node *receiver);
119 void replace_receiver(Node *old_receiver, Node *new_receiver);
120 void replace_sender(Node *new_sender, Node *receiver);
121 void insert_node_between(Node *sender, Node *middle, Node *receiver);
124 // Fits a rectangle of the given size to the current aspect ratio
125 // (aspect_nom/aspect_denom) and returns the new width and height.
126 unsigned fit_rectangle_to_aspect(unsigned width, unsigned height);
128 // Compute the input sizes for all inputs for all effects in a given phase,
129 // and inform the effects about the results.
130 void inform_input_sizes(Phase *phase);
132 // Determine the preferred output size of a given phase.
133 // Requires that all input phases (if any) already have output sizes set.
134 void find_output_size(Phase *phase);
136 // Find all inputs eventually feeding into this effect that have
137 // output gamma different from GAMMA_LINEAR.
138 void find_all_nonlinear_inputs(Node *effect, std::vector<Node *> *nonlinear_inputs);
140 // Create a GLSL program computing the given effects in order.
141 Phase *compile_glsl_program(const std::vector<Node *> &inputs,
142 const std::vector<Node *> &effects);
144 // Create all GLSL programs needed to compute the given effect, and all outputs
145 // that depends on it (whenever possible).
146 void construct_glsl_programs(Node *output);
148 // Output the current graph to the given file in a Graphviz-compatible format;
149 // only useful for debugging.
150 void output_dot(const char *filename);
152 // Some of the graph algorithms assume that the nodes array is sorted
153 // topologically (inputs are always before outputs), but some operations
154 // (like graph rewriting) can change that. This function restores that order.
155 void sort_nodes_topologically();
156 void topological_sort_visit_node(Node *node, std::set<Node *> *visited_nodes, std::vector<Node *> *sorted_list);
158 // Used during finalize().
159 void propagate_gamma_and_color_space();
160 Node *find_output_node();
162 bool node_needs_colorspace_fix(Node *node);
163 void fix_internal_color_spaces();
164 void fix_output_color_space();
166 bool node_needs_gamma_fix(Node *node);
167 void fix_internal_gamma_by_asking_inputs(unsigned step);
168 void fix_internal_gamma_by_inserting_nodes(unsigned step);
169 void fix_output_gamma();
171 float aspect_nom, aspect_denom;
172 ImageFormat output_format;
174 std::vector<Node *> nodes;
175 std::map<Effect *, Node *> node_map;
177 std::vector<Input *> inputs; // Also contained in nodes.
180 std::vector<Phase *> phases;
182 GLenum format, bytes_per_pixel;
186 #endif // !defined(_EFFECT_CHAIN_H)