X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=blur_effect.h;h=7f92074b882b2b1b06c1e34128d97a2dc5a5cc6e;hp=0657136181066042391e91baf4e9672fb7f4ef02;hb=c9a573370a976df3675d4bd3195a49c854ab7db9;hpb=b5e3174594efe9a920621a68d3b28f5e44676d03 diff --git a/blur_effect.h b/blur_effect.h index 0657136..7f92074 100644 --- a/blur_effect.h +++ b/blur_effect.h @@ -1,20 +1,85 @@ #ifndef _BLUR_EFFECT_H #define _BLUR_EFFECT_H 1 +// A separable 2D blur implemented by a combination of mipmap filtering +// and convolution (essentially giving a convolution with a piecewise linear +// approximation to the true impulse response). +// +// Works in two passes; first horizontal, then vertical (BlurEffect, +// which is what the user is intended to use, instantiates two copies of +// SingleBlurPassEffect behind the scenes). + #include "effect.h" +class SingleBlurPassEffect; + class BlurEffect : public Effect { public: BlurEffect(); + + virtual std::string effect_type_id() const { return "BlurEffect"; } + + // We want this for the same reason as ResizeEffect; we could end up scaling + // down quite a lot. + virtual bool needs_texture_bounce() const { return true; } + virtual bool needs_mipmaps() const { return true; } + virtual bool needs_srgb_primaries() const { return false; } + + virtual void inform_input_size(unsigned input_num, unsigned width, unsigned height); + + virtual std::string output_fragment_shader() { + assert(false); + } + virtual void set_gl_state(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num) { + assert(false); + } + + virtual void rewrite_graph(EffectChain *graph, Node *self); + virtual bool set_float(const std::string &key, float value); + +private: + void update_radius(); + + float radius; + SingleBlurPassEffect *hpass, *vpass; + unsigned input_width, input_height; +}; + +class SingleBlurPassEffect : public Effect { +public: + // If parent is non-NULL, calls to inform_input_size will be forwarded + // so that it can make reasonable decisions for both blur passes. + SingleBlurPassEffect(BlurEffect *parent); + virtual std::string effect_type_id() const { return "SingleBlurPassEffect"; } + std::string output_fragment_shader(); - virtual bool needs_many_samples() const { return true; } + virtual bool needs_texture_bounce() const { return true; } virtual bool needs_mipmaps() const { return true; } + virtual bool needs_srgb_primaries() const { return false; } + + virtual void inform_input_size(unsigned input_num, unsigned width, unsigned height) { + if (parent != NULL) { + parent->inform_input_size(input_num, width, height); + } + } + virtual bool changes_output_size() const { return true; } + + virtual void get_output_size(unsigned *width, unsigned *height) const { + *width = this->width; + *height = this->height; + } - void set_uniforms(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num); + void set_gl_state(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num); + void clear_gl_state(); + + enum Direction { HORIZONTAL = 0, VERTICAL = 1 }; private: + BlurEffect *parent; float radius; + Direction direction; + int width, height; }; #endif // !defined(_BLUR_EFFECT_H)