-#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.
+//
+// Threading considerations: EffectChain is “thread-compatible”; you can use
+// different EffectChains in multiple threads at the same time (assuming the
+// threads do not use the same OpenGL context, but this is a good idea anyway),
+// but you may not use one EffectChain from multiple threads simultaneously.
+// You _are_ allowed to use one EffectChain from multiple threads as long as
+// you only use it from one at a time (possibly by doing your own locking),
+// but if so, the threads' contexts need to be set up to share resources, since
+// the EffectChain holds textures and other OpenGL objects that are tied to the
+// context.
+
+#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;
+namespace movit {
+
+class Effect;
+class Input;
+struct Phase;
+class ResourcePool;
+
+// 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 {
std::vector<Node *> incoming_links;
private:
- // 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.
// they will be equal.
unsigned output_width, output_height;
- // If output goes to RTT (otherwise, none of these are set).
- // 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;
+ // If output goes to RTT, which phase it is in (otherwise unset).
+ // This is a bit ugly; we should probably fix so that Phase takes other
+ // phases as inputs, instead of Node.
Phase *phase;
+ // If the effect has is_single_texture(), or if the output went to RTT
+ // and that texture has been bound to a sampler, the sampler number
+ // will be stored here.
+ //
+ // TODO: Can an RTT texture be used as inputs to multiple effects
+ // within the same phase? If so, we have a problem with modifying
+ // sampler state here.
+ int bound_sampler_num;
+
// 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, vertex_shader, fragment_shader;
+ GLuint glsl_program_num; // Owned by the resource_pool.
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;
+
+ // Identifier used to create unique variables in GLSL.
+ // Unique per-phase to increase cacheability of compiled shaders.
+ std::map<Node *, std::string> effect_ids;
};
class EffectChain {
public:
- EffectChain(float aspect_nom, float aspect_denom); // E.g., 16.0f, 9.0f for 16:9.
+ // Aspect: e.g. 16.0f, 9.0f for 16:9.
+ // resource_pool is a pointer to a ResourcePool with which to share shaders
+ // and other resources (see resource_pool.h). If NULL (the default),
+ // will create its own that is not shared with anything else. Does not take
+ // ownership of the passed-in ResourcePool, but will naturally take ownership
+ // of its own internal one if created.
+ EffectChain(float aspect_nom, float aspect_denom, ResourcePool *resource_pool = NULL);
~EffectChain();
// User API:
}
Effect *add_effect(Effect *effect, const std::vector<Effect *> &inputs);
- void add_output(const ImageFormat &format);
+ 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 finalize();
+
//void render(unsigned char *src, unsigned char *dst);
void render_to_screen()
{
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);
+ Node *find_node_for_effect(Effect *effect) { return node_map[effect]; }
+
+ // Get the OpenGL sampler (GL_TEXTURE0, GL_TEXTURE1, etc.) for the
+ // input of the given node, so that one can modify the sampler state
+ // directly. Only valid to call during set_gl_state().
+ //
+ // Also, for this to be allowed, <node>'s effect must have
+ // needs_texture_bounce() set, so that it samples directly from a
+ // single-sampler input, or from an RTT texture.
+ GLenum get_input_sampler(Node *node, unsigned input_num) const;
+
+ // Get the current resource pool assigned to this EffectChain.
+ // Primarily to let effects allocate textures as needed.
+ // Any resources you get from the pool must be returned to the pool
+ // no later than in the Effect's destructor.
+ ResourcePool *get_resource_pool() { return resource_pool; }
private:
- // Fits a rectangle of the given size to the current aspect ratio
- // (aspect_nom/aspect_denom) and returns the new width and height.
- unsigned fit_rectangle_to_aspect(unsigned width, unsigned height);
+ // 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.
// 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_nodes_topologically();
- void topological_sort_visit_node(Node *node, std::set<Node *> *visited_nodes, std::vector<Node *> *sorted_list);
+ 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();
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;
+
+ ResourcePool *resource_pool;
+ bool owns_resource_pool;
};
-#endif // !defined(_EFFECT_CHAIN_H)
+} // namespace movit
+
+#endif // !defined(_MOVIT_EFFECT_CHAIN_H)
projects / movit / blobdiff