X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=blur_effect.h;h=b68094755bfe6188c801ebfbae222cd89870a0a6;hp=ee890c25543fa41599e67d3e9284bfd68d8ee196;hb=b5986420fc150a8c54e907fe7fdd7b89d6e93b55;hpb=b618b34070d23b6da35c77f004678d8a9e55575b

diff --git a/blur_effect.h b/blur_effect.h
index ee890c2..b680947 100644
--- a/blur_effect.h
+++ b/blur_effect.h
@@ -1,6 +1,14 @@
 #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;
@@ -9,37 +17,70 @@ 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 AlphaHandling alpha_handling() const { return INPUT_AND_OUTPUT_ALPHA_PREMULTIPLIED; }
+
+	virtual void inform_input_size(unsigned input_num, unsigned width, unsigned height);
+
 	virtual std::string output_fragment_shader() {
 		assert(false);
 	}
-	virtual void set_uniforms(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num) {
+	virtual void set_gl_state(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num) {
 		assert(false);
 	}
 
-	virtual bool needs_many_samples() const { return true; }
-	virtual bool needs_mipmaps() const { return true; }
-	virtual void add_self_to_effect_chain(std::vector<Effect *> *chain);
+	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:
-	SingleBlurPassEffect();
+	// 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)