-#ifndef _EFFECT_CHAIN_H
-#define _EFFECT_CHAIN_H 1
-
+#ifndef _MOVIT_EFFECT_CHAIN_H
+#define _MOVIT_EFFECT_CHAIN_H 1
+
+// An EffectChain is the largest basic entity in Movit; it contains everything
+// needed to connects a series of effects, from inputs to outputs, and render
+// them. Generally you set up your effect chain once and then call its render
+// functions once per frame; setting one up can be relatively expensive,
+// but rendering is fast.
+
+#include <GL/glew.h>
+#include <stdio.h>
+#include <map>
#include <set>
+#include <string>
#include <vector>
-#include "effect.h"
#include "image_format.h"
-#include "input.h"
-class EffectChain;
-class Phase;
+class Effect;
+class Input;
+struct Phase;
+
+// For internal use within Node.
+enum AlphaType {
+ ALPHA_INVALID = -1,
+ ALPHA_BLANK,
+ ALPHA_PREMULTIPLIED,
+ ALPHA_POSTMULTIPLIED,
+};
+
+// Whether you want pre- or postmultiplied alpha in the output
+// (see effect.h for a discussion of pre- versus postmultiplied alpha).
+enum OutputAlphaFormat {
+ OUTPUT_ALPHA_FORMAT_PREMULTIPLIED,
+ OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED,
+};
// A node in the graph; basically an effect and some associated information.
class Node {
public:
Effect *effect;
+ bool disabled;
// Edges in the graph (forward and backward).
std::vector<Node *> outgoing_links;
// Identifier used to create unique variables in GLSL.
std::string effect_id;
+ // Logical size of the output of this effect, ie. the resolution
+ // you would get if you sampled it as a texture. If it is undefined
+ // (since the inputs differ in resolution), it will be 0x0.
+ // If both this and output_texture_{width,height} are set,
+ // they will be equal.
+ unsigned output_width, output_height;
+
// If output goes to RTT (otherwise, none of these are set).
- // The Phsae pointer is a but ugly; we should probably fix so
+ // The Phase pointer is a but ugly; we should probably fix so
// that Phase takes other phases as inputs, instead of Node.
GLuint output_texture;
unsigned output_texture_width, output_texture_height;
Phase *phase;
// Used during the building of the effect chain.
- ColorSpace output_color_space;
+ Colorspace output_color_space;
GammaCurve output_gamma_curve;
+ AlphaType output_alpha_type;
friend class EffectChain;
};
// A rendering phase; a single GLSL program rendering a single quad.
struct Phase {
- GLint glsl_program_num;
+ GLint glsl_program_num, vertex_shader, fragment_shader;
bool input_needs_mipmaps;
// Inputs are only inputs from other phases (ie., those that come from RTT);
std::vector<Node *> inputs;
std::vector<Node *> effects; // In order.
- unsigned output_width, output_height;
+ unsigned output_width, output_height, virtual_output_width, virtual_output_height;
};
class EffectChain {
public:
- EffectChain(unsigned width, unsigned height);
+ EffectChain(float aspect_nom, float aspect_denom); // E.g., 16.0f, 9.0f for 16:9.
+ ~EffectChain();
// User API:
// input, effects, output, finalize need to come in that specific order.
}
Effect *add_effect(Effect *effect, const std::vector<Effect *> &inputs);
- // Similar to add_effect, but:
- //
- // * Does not insert any normalizing effects.
- // * Does not ask the effect to insert itself, so it won't work
- // with meta-effects.
- //
- // We should really separate out these two “sides” of Effect in the
- // type system soon.
- void add_effect_raw(Effect *effect, const std::vector<Effect *> &inputs);
+ void add_output(const ImageFormat &format, OutputAlphaFormat alpha_format);
+
+ // Set number of output bits, to scale the dither.
+ // 8 is the right value for most outputs.
+ // The default, 0, is a special value that means no dither.
+ void set_dither_bits(unsigned num_bits)
+ {
+ this->num_dither_bits = num_bits;
+ }
- void add_output(const ImageFormat &format);
void finalize();
+
//void render(unsigned char *src, unsigned char *dst);
- void render_to_screen();
+ void render_to_screen()
+ {
+ render_to_fbo(0, 0, 0);
+ }
+
+ // Render the effect chain to the given FBO. If width=height=0, keeps
+ // the current viewport.
+ void render_to_fbo(GLuint fbo, unsigned width, unsigned height);
Effect *last_added_effect() {
if (nodes.empty()) {
}
}
+ // API for manipulating the graph directly. Intended to be used from
+ // effects and by EffectChain itself.
+ //
+ // Note that for nodes with multiple inputs, the order of calls to
+ // connect_nodes() will matter.
+ Node *add_node(Effect *effect);
+ void connect_nodes(Node *sender, Node *receiver);
+ void replace_receiver(Node *old_receiver, Node *new_receiver);
+ void replace_sender(Node *new_sender, Node *receiver);
+ void insert_node_between(Node *sender, Node *middle, Node *receiver);
+
private:
+ // Make sure the output rectangle is at least large enough to hold
+ // the given input rectangle in both dimensions, and is of the
+ // current aspect ratio (aspect_nom/aspect_denom).
+ void size_rectangle_to_fit(unsigned width, unsigned height, unsigned *output_width, unsigned *output_height);
+
+ // Compute the input sizes for all inputs for all effects in a given phase,
+ // and inform the effects about the results.
+ void inform_input_sizes(Phase *phase);
+
// Determine the preferred output size of a given phase.
// Requires that all input phases (if any) already have output sizes set.
void find_output_size(Phase *phase);
- void find_all_nonlinear_inputs(Node *effect,
- std::vector<Node *> *nonlinear_inputs,
- std::vector<Node *> *intermediates);
- Node *normalize_to_linear_gamma(Node *input);
- Node *normalize_to_srgb(Node *input);
+ // Find all inputs eventually feeding into this effect that have
+ // output gamma different from GAMMA_LINEAR.
+ void find_all_nonlinear_inputs(Node *effect, std::vector<Node *> *nonlinear_inputs);
// Create a GLSL program computing the given effects in order.
Phase *compile_glsl_program(const std::vector<Node *> &inputs,
// that depends on it (whenever possible).
void construct_glsl_programs(Node *output);
- unsigned width, height;
+ // Output the current graph to the given file in a Graphviz-compatible format;
+ // only useful for debugging.
+ void output_dot(const char *filename);
+ std::vector<std::string> get_labels_for_edge(const Node *from, const Node *to);
+ void output_dot_edge(FILE *fp,
+ const std::string &from_node_id,
+ const std::string &to_node_id,
+ const std::vector<std::string> &labels);
+
+ // Some of the graph algorithms assume that the nodes array is sorted
+ // topologically (inputs are always before outputs), but some operations
+ // (like graph rewriting) can change that. This function restores that order.
+ void sort_all_nodes_topologically();
+
+ // Do the actual topological sort. <nodes> must be a connected, acyclic subgraph;
+ // links that go to nodes not in the set will be ignored.
+ std::vector<Node *> topological_sort(const std::vector<Node *> &nodes);
+
+ // Utility function used by topological_sort() to do a depth-first search.
+ // The reason why we store nodes left to visit instead of a more conventional
+ // list of nodes to visit is that we want to be able to limit ourselves to
+ // a subgraph instead of all nodes. The set thus serves a dual purpose.
+ void topological_sort_visit_node(Node *node, std::set<Node *> *nodes_left_to_visit, std::vector<Node *> *sorted_list);
+
+ // Used during finalize().
+ void find_color_spaces_for_inputs();
+ void propagate_alpha();
+ void propagate_gamma_and_color_space();
+ Node *find_output_node();
+
+ bool node_needs_colorspace_fix(Node *node);
+ void fix_internal_color_spaces();
+ void fix_output_color_space();
+
+ bool node_needs_alpha_fix(Node *node);
+ void fix_internal_alpha(unsigned step);
+ void fix_output_alpha();
+
+ bool node_needs_gamma_fix(Node *node);
+ void fix_internal_gamma_by_asking_inputs(unsigned step);
+ void fix_internal_gamma_by_inserting_nodes(unsigned step);
+ void fix_output_gamma();
+ void add_dither_if_needed();
+
+ float aspect_nom, aspect_denom;
ImageFormat output_format;
+ OutputAlphaFormat output_alpha_format;
std::vector<Node *> nodes;
std::map<Effect *, Node *> node_map;
+ Effect *dither_effect;
std::vector<Input *> inputs; // Also contained in nodes.
-
- GLuint fbo;
std::vector<Phase *> phases;
- GLenum format, bytes_per_pixel;
+ unsigned num_dither_bits;
bool finalized;
};
-#endif // !defined(_EFFECT_CHAIN_H)
+#endif // !defined(_MOVIT_EFFECT_CHAIN_H)