X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=blur_effect.h;h=d97f5bdcd2b05352c331ddafb552783444ac8235;hp=0657136181066042391e91baf4e9672fb7f4ef02;hb=131e7179b596f8268fd80c32312849da83581e55;hpb=b5e3174594efe9a920621a68d3b28f5e44676d03

diff --git a/blur_effect.h b/blur_effect.h
index 0657136..d97f5bd 100644
--- a/blur_effect.h
+++ b/blur_effect.h
@@ -1,20 +1,99 @@
-#ifndef _BLUR_EFFECT_H
-#define _BLUR_EFFECT_H 1
+#ifndef _MOVIT_BLUR_EFFECT_H
+#define _MOVIT_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 <GL/glew.h>
+#include <assert.h>
+#include <stddef.h>
+#include <string>
 
 #include "effect.h"
 
+namespace movit {
+
+class EffectChain;
+class Node;
+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 AlphaHandling alpha_handling() const { return INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK; }
+
+	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; }
 
-	void set_uniforms(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num);
+	virtual void get_output_size(unsigned *width, unsigned *height, unsigned *virtual_width, unsigned *virtual_height) const {
+		*width = this->width;
+		*height = this->height;
+		*virtual_width = this->virtual_width;
+		*virtual_height = this->virtual_height;
+	}
+
+	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, virtual_width, virtual_height;
 };
 
-#endif // !defined(_BLUR_EFFECT_H)
+}  // namespace movit
+
+#endif // !defined(_MOVIT_BLUR_EFFECT_H)