X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=effect.h;h=9d4f247632449cbb2cccaf44000d75343b4b147c;hp=db0fa94d43397804194021c910419363e826d14e;hb=d41e82b7cc456c945dbc460b2ffdc13a80f6505f;hpb=2c9711e213679e11bea1b0e86bb46af442b22ee0 diff --git a/effect.h b/effect.h index db0fa94..9d4f247 100644 --- a/effect.h +++ b/effect.h @@ -1,5 +1,5 @@ -#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. @@ -10,16 +10,13 @@ // effect instance; use the macro PREFIX() around your identifiers to // automatically prepend that prefix. +#include +#include +#include #include #include -#include - -#include -#include - -#include "opengl.h" -#include "util.h" +#include "defs.h" class EffectChain; class Node; @@ -40,14 +37,13 @@ struct RGBTriplet { float r, g, b; }; -// Convenience functions that deal with prepending the prefix. -GLint get_uniform_location(GLuint glsl_program_num, const std::string &prefix, const std::string &key); -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_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); -void set_uniform_mat3(GLuint glsl_program_num, const std::string &prefix, const std::string &key, const Eigen::Matrix3d &matrix); +// Can alias on a float[4]. +struct RGBATuple { + RGBATuple(float r, float g, float b, float a) + : r(r), g(g), b(b), a(a) {} + + float r, g, b, a; +}; class Effect { public: @@ -78,6 +74,60 @@ public: // in a linear fashion. virtual bool needs_srgb_primaries() const { return true; } + // 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 thare 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 @@ -116,11 +166,16 @@ public: virtual bool changes_output_size() const { return false; } // If changes_output_size() is true, you must implement this to tell - // the framework what output size you want. + // 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) const { + virtual void get_output_size(unsigned *width, unsigned *height, + unsigned *virtual_width, unsigned *virtual_height) const { assert(false); } @@ -179,10 +234,11 @@ public: // 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); - 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); + 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: // Register a parameter. Whenever set_*() is called with the same key, @@ -195,10 +251,11 @@ protected: // Thus, ints that you register will _not_ be converted to GLSL uniforms. void register_int(const std::string &key, int *value); - // These correspond directly to float/vec2/vec3 in GLSL. + // These correspond directly to float/vec2/vec3/vec4 in GLSL. 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_vec4(const std::string &key, float *values); // This will register a 1D texture, which will be bound to a sampler // when your GLSL code runs (so it corresponds 1:1 to a sampler2D uniform @@ -223,7 +280,8 @@ private: std::map params_float; std::map params_vec2; std::map params_vec3; + std::map params_vec4; std::map params_tex_1d; }; -#endif // !defined(_EFFECT_H) +#endif // !defined(_MOVIT_EFFECT_H)