X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=effect_chain.h;h=ddabad959bb292b7798af46e69c6869ccca1c1c5;hp=6ceb0c361f80e4b1d94db6d5db1a5a775979f925;hb=ad66f9714e4a36008c341355700272a52484a785;hpb=a616ded3842994840ce0cfa365d259f602493779

diff --git a/effect_chain.h b/effect_chain.h
index 6ceb0c3..ddabad9 100644
--- a/effect_chain.h
+++ b/effect_chain.h
@@ -1,15 +1,33 @@
 #ifndef _EFFECT_CHAIN_H
 #define _EFFECT_CHAIN_H 1
 
+#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 {
@@ -42,6 +60,7 @@ private:
 	// Used during the building of the effect chain.
 	Colorspace output_color_space;
 	GammaCurve output_gamma_curve;
+	AlphaType output_alpha_type;
 
 	friend class EffectChain;
 };
@@ -56,7 +75,7 @@ struct Phase {
 	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 {
@@ -89,7 +108,7 @@ public:
 	}
 	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.
@@ -132,9 +151,10 @@ public:
 	void insert_node_between(Node *sender, Node *middle, Node *receiver);
 
 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.	
@@ -159,15 +179,30 @@ private:
 	// 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();
 
@@ -175,6 +210,10 @@ private:
 	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);
@@ -183,6 +222,7 @@ private:
 
 	float aspect_nom, aspect_denom;
 	ImageFormat output_format;
+	OutputAlphaFormat output_alpha_format;
 
 	std::vector<Node *> nodes;
 	std::map<Effect *, Node *> node_map;
@@ -193,8 +233,7 @@ private:
 	GLuint fbo;
 	std::vector<Phase *> phases;
 
-	GLenum format;
-	unsigned bytes_per_pixel, num_dither_bits;
+	unsigned num_dither_bits;
 	bool finalized;
 };