X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=effect.h;h=073780f172bdbc929db64238c1705221264691c4;hp=cd6f00882d91e0a9086c5f691a473801a132dfe7;hb=65c6584f77bff0af0c8e38d1ac90298bcd55e9ac;hpb=b618b34070d23b6da35c77f004678d8a9e55575b diff --git a/effect.h b/effect.h index cd6f008..073780f 100644 --- a/effect.h +++ b/effect.h @@ -1,14 +1,33 @@ -#ifndef _EFFECT_H -#define _EFFECT_H 1 +#ifndef _MOVIT_EFFECT_H +#define _MOVIT_EFFECT_H 1 +// Effect is the base class for every effect. It basically represents a single +// GLSL function, with an optional set of user-settable parameters. +// +// A note on naming: Since all effects run in the same GLSL namespace, +// you can't use any name you want for global variables (e.g. uniforms). +// The framework assigns a prefix to you which will be unique for each +// effect instance; use the macro PREFIX() around your identifiers to +// automatically prepend that prefix. + +#include +#include +#include #include #include #include +#include + +#include "defs.h" + +namespace movit { -#include +class EffectChain; +class Node; // Can alias on a float[2]. struct Point2D { + Point2D() {} Point2D(float x, float y) : x(x), y(y) {} @@ -17,63 +36,389 @@ struct Point2D { // Can alias on a float[3]. struct RGBTriplet { + RGBTriplet() {} RGBTriplet(float r, float g, float b) : r(r), g(g), b(b) {} float r, g, b; }; -// Convenience functions that deal with prepending the prefix. -void set_uniform_int(GLuint glsl_program_num, const std::string &prefix, const std::string &key, int value); -void set_uniform_float(GLuint glsl_program_num, const std::string &prefix, const std::string &key, float value); -void set_uniform_float_array(GLuint glsl_program_num, const std::string &prefix, const std::string &key, const float *values, size_t num_values); -void set_uniform_vec2(GLuint glsl_program_num, const std::string &prefix, const std::string &key, const float *values); -void set_uniform_vec3(GLuint glsl_program_num, const std::string &prefix, const std::string &key, const float *values); -void set_uniform_vec4_array(GLuint glsl_program_num, const std::string &prefix, const std::string &key, const float *values, size_t num_values); +// Can alias on a float[4]. +struct RGBATuple { + RGBATuple() {} + RGBATuple(float r, float g, float b, float a) + : r(r), g(g), b(b), a(a) {} + + float r, g, b, a; +}; + +// Represents a registered uniform. +template +struct Uniform { + std::string name; // Without prefix. + const T *value; // Owner by the effect. + size_t num_values; // Number of elements; for arrays only. _Not_ the vector length. + std::string prefix; // Filled in only after phases have been constructed. + GLint location; // Filled in only after phases have been constructed. -1 if no location. +}; class Effect { -public: +public: + virtual ~Effect() {} + + // An identifier for this type of effect, mostly used for debug output + // (but some special names, like "ColorspaceConversionEffect", holds special + // meaning). Same as the class name is fine. + virtual std::string effect_type_id() const = 0; + + // Whether this effects expects its input (and output) to be in + // linear gamma, ie. without an applied gamma curve. Most effects + // will want this, although the ones that never actually look at + // the pixels, e.g. mirror, won't need to care, and can set this + // to false. If so, the input gamma will be undefined. + // + // Also see the note on needs_texture_bounce(), below. virtual bool needs_linear_light() const { return true; } + + // Whether this effect expects its input to be in the sRGB + // color space, ie. use the sRGB/Rec. 709 RGB primaries. + // (If not, it would typically come in as some slightly different + // set of RGB primaries; you would currently not get YCbCr + // or something similar). + // + // Again, most effects will want this, but you can set it to false + // if you process each channel independently, equally _and_ + // in a linear fashion. virtual bool needs_srgb_primaries() const { return true; } - virtual bool needs_many_samples() const { return false; } + + // How this effect handles alpha, ie. what it outputs in its + // alpha channel. The choices are basically blank (alpha is always 1.0), + // premultiplied and postmultiplied. + // + // Premultiplied alpha is when the alpha value has been be multiplied + // into the three color components, so e.g. 100% red at 50% alpha + // would be (0.5, 0.0, 0.0, 0.5) instead of (1.0, 0.0, 0.0, 0.5) + // as it is stored in most image formats (postmultiplied alpha). + // The multiplication is taken to have happened in linear light. + // This is the most natural format for processing, and the default in + // most of Movit (just like linear light is). + // + // If you set INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA or + // INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK, all of your inputs + // (if any) are guaranteed to also be in premultiplied alpha. + // Otherwise, you can get postmultiplied or premultiplied alpha; + // you won't know. If you have multiple inputs, you will get the same + // (pre- or postmultiplied) for all inputs, although most likely, + // you will want to combine them in a premultiplied fashion anyway + // in that case. + enum AlphaHandling { + // Always outputs blank alpha (ie. alpha=1.0). Only appropriate + // for inputs that do not output an alpha channel. + // Blank alpha is special in that it can be treated as both + // pre- and postmultiplied. + OUTPUT_BLANK_ALPHA, + + // Always outputs postmultiplied alpha. Only appropriate for inputs. + OUTPUT_POSTMULTIPLIED_ALPHA, + + // Always outputs premultiplied alpha. As noted above, + // you will then also get all inputs in premultiplied alpha. + // If you set this, you should also set needs_linear_light(). + INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA, + + // Like INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA, but also guarantees + // that if you get blank alpha in, you also keep blank alpha out. + // This is a somewhat weaker guarantee than DONT_CARE_ALPHA_TYPE, + // but is still useful in many situations, and appropriate when + // e.g. you don't touch alpha at all. + // + // Does not make sense for inputs. + INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK, + + // Keeps the type of alpha (premultiplied, postmultiplied, blank) + // unchanged from input to output. Usually appropriate if you + // process all color channels in a linear fashion, do not change + // alpha, and do not produce any new pixels that have alpha != 1.0. + // + // Does not make sense for inputs. + DONT_CARE_ALPHA_TYPE, + }; + virtual AlphaHandling alpha_handling() const { return INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA; } + + // Whether this effect expects its input to come directly from + // a texture. If this is true, the framework will not chain the + // input from other effects, but will store the results of the + // chain to a temporary (RGBA fp16) texture and let this effect + // sample directly from that. + // + // There are two good reasons why you might want to set this: + // + // 1. You are sampling more than once from the input, + // in which case computing all the previous steps might + // be more expensive than going to a memory intermediate. + // 2. You rely on previous effects, possibly including gamma + // expansion, to happen pre-filtering instead of post-filtering. + // (This is only relevant if you actually need the filtering; if + // you sample 1:1 between pixels and texels, it makes no difference.) + // + // Note that in some cases, you might get post-filtered gamma expansion + // even when setting this option. More specifically, if you are the + // first effect in the chain, and the GPU is doing sRGB gamma + // expansion, it is undefined (from OpenGL's side) whether expansion + // happens pre- or post-filtering. For most uses, however, + // either will be fine. + virtual bool needs_texture_bounce() const { return false; } + + // Whether this effect expects mipmaps or not. If you set this to + // true, you will be sampling with bilinear filtering; if not, + // you could be sampling with simple linear filtering and no mipmaps + // (although there is no guarantee; if a different effect in the chain + // needs mipmaps, you will also get them). virtual bool needs_mipmaps() const { return false; } - virtual void add_self_to_effect_chain(std::vector *chain) { - chain->push_back(this); + + // Whether there is a direct correspondence between input and output + // texels. Specifically, the effect must not: + // + // 1. Try to sample in the border (ie., outside the 0.0 to 1.0 area). + // 2. Try to sample between texels. + // 3. Sample with an x- or y-derivative different from -1 or 1. + // (This also means needs_mipmaps() and one_to_one_sampling() + // together would make no sense.) + // + // The most common case for this would be an effect that has an exact + // 1:1-correspondence between input and output texels, e.g. SaturationEffect. + // However, more creative things, like mirroring/flipping or padding, + // would also be allowed. + // + // The primary gain from setting this is that you can sample directly + // from an effect that changes output size (see changes_output_size() below), + // without going through a bounce texture. It won't work for effects that + // set sets_virtual_output_size(), though. + // + // Does not make a lot of sense together with needs_texture_bounce(). + virtual bool one_to_one_sampling() const { return false; } + + // Whether this effect wants to output to a different size than + // its input(s) (see inform_input_size(), below). See also + // sets_virtual_output_size() below. + virtual bool changes_output_size() const { return false; } + + // Whether your get_output_size() function (see below) intends to ever set + // virtual_width different from width, or similar for height. + // It does not make sense to set this to true if changes_output_size() is false. + virtual bool sets_virtual_output_size() const { return changes_output_size(); } + + // Whether this effect is effectively sampling from a a single texture. + // If so, it will override needs_texture_bounce(); however, there are also + // two demands it needs to fulfill: + // + // 1. It needs to be an Input, ie. num_inputs() == 0. + // 2. It needs to allocate exactly one sampler in set_gl_state(), + // and allow dependent effects to change that sampler state. + virtual bool is_single_texture() const { return false; } + + // If set, this effect should never be bounced to an output, even if a + // dependent effect demands texture bounce. + // + // Note that setting this can invoke undefined behavior, up to and including crashing, + // so you should only use it if you have deep understanding of your entire chain + // and Movit's processing of it. The most likely use case is if you have an input + // that's cheap to compute but not a single texture (e.g. YCbCrInput), and want + // to run a ResampleEffect directly from it. Normally, this would require a bounce, + // but it's faster not to. (However, also note that in this case, effective texel + // subpixel precision will be too optimistic, since chroma is already subsampled.) + // + // Has no effect if is_single_texture() is set. + virtual bool override_disable_bounce() const { return false; } + + // If changes_output_size() is true, you must implement this to tell + // the framework what output size you want. Also, you can set a + // virtual width/height, which is the size the next effect (if any) + // will _think_ your data is in. This is primarily useful if you are + // relying on getting OpenGL's bilinear resizing for free; otherwise, + // your virtual_width/virtual_height should be the same as width/height. + // + // Note that it is explicitly allowed to change width and height + // from frame to frame; EffectChain will reallocate textures as needed. + virtual void get_output_size(unsigned *width, unsigned *height, + unsigned *virtual_width, unsigned *virtual_height) const { + assert(false); + } + + // Whether this effect uses a compute shader instead of a regular fragment shader. + // Compute shaders are more flexible in that they can have multiple outputs + // for each invocation and also communicate between instances (by using shared + // memory within each group), but are not universally supported. The typical + // pattern would be to check movit_compute_shaders_supported and rewrite the + // graph to use a compute shader effect instead of a regular effect if it is + // available, in order to get better performance. Since compute shaders can reuse + // loads (again typically through shared memory), using needs_texture_bounce() + // is usually not needed, although it is allowed; the best candidates for compute + // shaders are typically those that sample many times from their input + // but can reuse those loads across neighboring instances. + // + // Compute shaders commonly work with unnormalized texture coordinates + // (where coordinates are integers [0..W) and [0..H)), whereas the rest + // of Movit, including any inputs you may want to sample from, works + // with normalized coordinates ([0..1)). Movit gives you uniforms + // PREFIX(inv_output_size) and PREFIX(output_texcoord_adjust) that you + // can use to transform unnormalized to normalized, as well as a macro + // NORMALIZE_TEXTURE_COORDS(vec2) that does it for you. + // + // Since compute shaders have flexible output, it is difficult to chain other + // effects after them in the same phase, and thus, they will always be last. + // (This limitation may be lifted for the special case of one-to-one effects + // in the future.) Furthermore, they cannot write to the framebuffer, just to + // textures, so Movit may have to insert an extra phase just to do the output + // from a texture to the screen in some cases. However, this is transparent + // to both the effect and the user. + virtual bool is_compute_shader() const { return false; } + + // For a compute shader (see the previous member function), what dimensions + // it should be invoked over. Called every frame, before uniforms are set + // (so you are allowed to update uniforms based from this call). + virtual void get_compute_dimensions(unsigned output_width, unsigned output_height, + unsigned *x, unsigned *y, unsigned *z) const { + *x = output_width; + *y = output_height; + *z = 1; } - virtual std::string output_convenience_uniforms() const; + // Tells the effect the resolution of each of its input. + // This will be called every frame, and always before get_output_size(), + // so you can change your output size based on the input if so desired. + // + // Note that in some cases, an input might not have a single well-defined + // resolution (for instance if you fade between two inputs with + // different resolutions). In this case, you will get width=0 and height=0 + // for that input. If you cannot handle that, you will need to set + // needs_texture_bounce() to true, which will force a render to a single + // given resolution before you get the input. + virtual void inform_input_size(unsigned input_num, unsigned width, unsigned height) {} + + // How many inputs this effect will take (a fixed number). + // If you have only one input, it will be called INPUT() in GLSL; + // if you have several, they will be INPUT1(), INPUT2(), and so on. + virtual unsigned num_inputs() const { return 1; } + + // Inform the effect that it has been just added to the EffectChain. + // The primary use for this is to store the ResourcePool uesd by + // the chain; for modifications to it, rewrite_graph() below + // is probably a better fit. + virtual void inform_added(EffectChain *chain) {} + + // Let the effect rewrite the effect chain as it sees fit. + // Most effects won't need to do this, but this is very useful + // if you have an effect that consists of multiple sub-effects + // (for instance, two passes). The effect is given to its own + // pointer, and it can add new ones (by using add_node() + // and connect_node()) as it sees fit. This is called at + // EffectChain::finalize() time, when the entire graph is known, + // in the order that the effects were originally added. + // + // Note that if the effect wants to take itself entirely out + // of the chain, it must set “disabled” to true and then disconnect + // itself from all other effects. + virtual void rewrite_graph(EffectChain *graph, Node *self) {} + + // Returns the GLSL fragment shader string for this effect. virtual std::string output_fragment_shader() = 0; - virtual void set_uniforms(GLuint glsl_program_num, const std::string& prefix, unsigned *sampler_num); + // Set all OpenGL state that this effect needs before rendering. + // The default implementation sets one uniform per registered parameter, + // but no other state. + // + // is the first free texture sampler. If you want to use + // textures, you can bind a texture to GL_TEXTURE0 + , + // and then increment the number (so that the next effect in the chain + // will use a different sampler). + virtual void set_gl_state(GLuint glsl_program_num, const std::string& prefix, unsigned *sampler_num); + + // If you set any special OpenGL state in set_gl_state(), you can clear it + // after rendering here. The default implementation does nothing. + virtual void clear_gl_state(); - // Neither of these take ownership. - virtual bool set_int(const std::string&, int value); - virtual bool set_float(const std::string &key, float value); - virtual bool set_vec2(const std::string &key, const float *values); - virtual bool set_vec3(const std::string &key, const float *values); + // Set a parameter; intended to be called from user code. + // Neither of these take ownership of the pointer. + virtual bool set_int(const std::string&, int value) MUST_CHECK_RESULT; + virtual bool set_float(const std::string &key, float value) MUST_CHECK_RESULT; + virtual bool set_vec2(const std::string &key, const float *values) MUST_CHECK_RESULT; + virtual bool set_vec3(const std::string &key, const float *values) MUST_CHECK_RESULT; + virtual bool set_vec4(const std::string &key, const float *values) MUST_CHECK_RESULT; protected: - // Neither of these take ownership. + // Register a parameter. Whenever set_*() is called with the same key, + // it will update the value in the given pointer (typically a pointer + // to some private member variable in your effect). It will also + // register a uniform of the same name (plus an arbitrary prefix + // which you can access using the PREFIX macro) that you can access. + // + // Neither of these take ownership of the pointer. + + // These correspond directly to int/float/vec2/vec3/vec4 in GLSL. void register_int(const std::string &key, int *value); void register_float(const std::string &key, float *value); void register_vec2(const std::string &key, float *values); void register_vec3(const std::string &key, float *values); - void register_1d_texture(const std::string &key, float *values, size_t size); - void invalidate_1d_texture(const std::string &key); - -private: - struct Texture1D { - float *values; - size_t size; - bool needs_update; - GLuint texture_num; - }; + void register_vec4(const std::string &key, float *values); + // Register uniforms, such that they will automatically be set + // before the shader runs. This is more efficient than set_uniform_* + // in effect_util.h, because it doesn't need to do name lookups + // every time. Also, in the future, it will use uniform buffer objects + // (UBOs) if available to reduce the number of calls into the driver. + // + // May not be called after output_fragment_shader() has returned. + // The pointer must be valid for the entire lifetime of the Effect, + // since the value is pulled from it each execution. The value is + // guaranteed to be read after set_gl_state() for the effect has + // returned, so you can safely update its value from there. + // + // Note that this will also declare the uniform in the shader for you, + // so you should not do that yourself. (This is so it can be part of + // the right uniform block.) However, it is probably a good idea to + // have a commented-out declaration so that it is easier to see the + // type and thus understand the shader on its own. + // + // Calling register_* will automatically imply register_uniform_*, + // except for register_int as noted above. + void register_uniform_sampler2d(const std::string &key, const int *value); + void register_uniform_bool(const std::string &key, const bool *value); + void register_uniform_int(const std::string &key, const int *value); // Note: Requires GLSL 1.30 or newer. + void register_uniform_float(const std::string &key, const float *value); + void register_uniform_vec2(const std::string &key, const float *values); + void register_uniform_vec3(const std::string &key, const float *values); + void register_uniform_vec4(const std::string &key, const float *values); + void register_uniform_float_array(const std::string &key, const float *values, size_t num_values); + void register_uniform_vec2_array(const std::string &key, const float *values, size_t num_values); + void register_uniform_vec3_array(const std::string &key, const float *values, size_t num_values); + void register_uniform_vec4_array(const std::string &key, const float *values, size_t num_values); + void register_uniform_mat3(const std::string &key, const Eigen::Matrix3d *matrix); + +private: std::map params_int; std::map params_float; std::map params_vec2; std::map params_vec3; - std::map params_tex_1d; + std::map params_vec4; + + // Picked out by EffectChain during finalization. + std::vector > uniforms_image2d; + std::vector > uniforms_sampler2d; + std::vector > uniforms_bool; + std::vector > uniforms_int; + std::vector > uniforms_float; + std::vector > uniforms_vec2; + std::vector > uniforms_vec3; + std::vector > uniforms_vec4; + std::vector > uniforms_float_array; + std::vector > uniforms_vec2_array; + std::vector > uniforms_vec3_array; + std::vector > uniforms_vec4_array; + std::vector > uniforms_mat3; + friend class EffectChain; }; -#endif // !defined(_EFFECT_H) +} // namespace movit + +#endif // !defined(_MOVIT_EFFECT_H)