+// RGBA output is nearly always packed; Y'CbCr, however, is often planar
+// due to chroma subsampling. This enum controls how add_ycbcr_output()
+// distributes the color channels between the fragment shader outputs.
+// Obviously, anything except YCBCR_OUTPUT_INTERLEAVED will be meaningless
+// unless you use render_to_fbo() and have an FBO with multiple render
+// targets attached (the other outputs will be discarded).
+enum YCbCrOutputSplitting {
+ // Only one output: Store Y'CbCr into the first three output channels,
+ // respectively, plus alpha. This is also called “chunked” or
+ // ”packed” mode.
+ YCBCR_OUTPUT_INTERLEAVED,
+
+ // Store Y' and alpha into the first output (in the red and alpha
+ // channels; effect to the others is undefined), and Cb and Cr into
+ // the first two channels of the second output. This is particularly
+ // useful if you want to end up in a format like NV12, where all the
+ // Y' samples come first and then Cb and Cr come interlevaed afterwards.
+ // You will still need to do the chroma subsampling yourself to actually
+ // get down to NV12, though.
+ YCBCR_OUTPUT_SPLIT_Y_AND_CBCR,
+
+ // Store Y' and alpha into the first output, Cb into the first channel
+ // of the second output and Cr into the first channel of the third output.
+ // (Effect on the other channels is undefined.) Essentially gives you
+ // 4:4:4 planar, or ”yuv444p”.
+ YCBCR_OUTPUT_PLANAR,
+};
+
+// 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;
+ std::vector<Node *> incoming_links;
+
+ // For unit tests only. Do not use from other code.
+ // Will contain an arbitrary choice if the node is in multiple phases.
+ Phase *containing_phase;
+
+private:
+ // 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 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;
+ GammaCurve output_gamma_curve;
+ AlphaType output_alpha_type;
+ bool needs_mipmaps; // Directly or indirectly.
+
+ // Set if this effect, and all effects consuming output from this node
+ // (in the same phase) have one_to_one_sampling() set.
+ bool one_to_one_sampling;
+
+ friend class EffectChain;
+};
+
+// A rendering phase; a single GLSL program rendering a single quad.
+struct Phase {
+ Node *output_node;
+
+ 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);
+ // input textures are counted as part of <effects>.
+ std::vector<Phase *> inputs;
+ // Bound sampler numbers for each input. Redundant in a sense
+ // (it always corresponds to the index), but we need somewhere
+ // to hold the value for the uniform.
+ std::vector<int> input_samplers;
+ std::vector<Node *> effects; // In order.
+ 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;
+
+ // Uniforms for this phase; combined from all the effects.
+ std::vector<Uniform<int> > uniforms_sampler2d;
+ std::vector<Uniform<bool> > uniforms_bool;
+ std::vector<Uniform<int> > uniforms_int;
+ std::vector<Uniform<float> > uniforms_float;
+ std::vector<Uniform<float> > uniforms_vec2;
+ std::vector<Uniform<float> > uniforms_vec3;
+ std::vector<Uniform<float> > uniforms_vec4;
+ std::vector<Uniform<Eigen::Matrix3d> > uniforms_mat3;
+
+ // For measurement of GPU time used.
+ GLuint timer_query_object;
+ uint64_t time_elapsed_ns;
+ uint64_t num_measured_iterations;