X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=blobdiff_plain;f=source%2Fcore%2Fframebuffer.h;h=5476596317000dbecd53eca3146adce3dcc4407c;hp=18e48f2022b6b1197129a6de6c57ee8a37cf38b3;hb=HEAD;hpb=160e9eea29bd10034733d59507fa1bcca36be401

diff --git a/source/core/framebuffer.h b/source/core/framebuffer.h
index 18e48f20..4932f29a 100644
--- a/source/core/framebuffer.h
+++ b/source/core/framebuffer.h
@@ -5,6 +5,7 @@
 #include "color.h"
 #include "framebuffer_backend.h"
 #include "frameformat.h"
+#include "rect.h"
 #include "texturecube.h"
 
 namespace Msp {
@@ -23,38 +24,41 @@ public:
 };
 
 /**
-Framebuffer objects can be used to perform offscreen rendering.  The most
-common application is rendering to a texture, which can then be used for
-fullscreen shader effects.
-
-A framebuffer consist of a number of logical buffers, such as color and depth
-buffers.  Textures can be attached to the logical buffers.  At least one image
-must be attached for the framebuffer to be usable.
-
-Requires the GL_EXT_framebuffer_object extension.  The blit functions require
-the GL_EXT_framebuffer_blit extension.
+Uses one or more textures as buffers to draw into.  Framebuffers can contain
+multiple color buffers to match multiple outputs from a fragment shader, but
+only one depth and stencil buffer.
+
+If a framebuffer has a multisampled format, each attachment can optionally have
+a single-sampled resolve attachment associated with it.  When a multisample
+resolve operation is performed on the framebuffer (such as by a Sequence), the
+sample values from the primary attachments are converted to a single value per
+pixel in the corresponding resolve attachments.
+
+RenderTarget provides a higher-level interface which manages the textures as
+well as the framebuffer itself.
 */
 class Framebuffer: public FramebufferBackend
 {
 	friend FramebufferBackend;
 
-private:
+protected:
 	struct Attachment
 	{
-		Texture *tex;
-		unsigned level;
-		int layer;
+		Texture *tex = 0;
+		Texture *resolve = 0;
+		unsigned level = 0;
+		int layer = 0;
 
-		Attachment();
-		void set(Texture &, unsigned, int);
+		void set(Texture &, Texture *, unsigned, int);
 		void clear();
 	};
 
 	FrameFormat format;
 	std::vector<Attachment> attachments;
-	unsigned width;
-	unsigned height;
-	mutable unsigned dirty;
+	unsigned width = 0;
+	unsigned height = 0;
+	unsigned layers = 0;
+	mutable unsigned dirty = 0;
 
 	Framebuffer(bool);
 public:
@@ -68,10 +72,6 @@ public:
 	/** Creates a framebuffer and sets its format. */
 	Framebuffer(const FrameFormat &);
 
-private:
-	void init();
-
-public:
 	/** Sets the format of the framebuffer.  Once the format is set, it can't
 	be changed. */
 	void set_format(const FrameFormat &);
@@ -80,27 +80,47 @@ public:
 
 	unsigned get_width() const { return width; }
 	unsigned get_height() const { return height; }
+	Rect get_rect() const { return Rect(0, 0, width, height); }
+	unsigned get_layers() const { return layers; }
 
-private:
+protected:
 	void update() const;
 	void check_size();
-	void set_attachment(FrameAttachment, Texture &, unsigned, int, unsigned);
-public:
+	void set_attachment(FrameAttachment, Texture &, Texture *, unsigned, int, unsigned);
 
+public:
 	/** Attaches a texture to the framebuffer.  Only the attachment point
 	portion of attch is considered; pixel format is ignored.  The framebuffer
 	must have a format and the format of the texture must match that defined
 	in the framebuffer for this attachment point. */
-	void attach(FrameAttachment attch, Texture2D &tex, unsigned level = 0);
+	void attach(FrameAttachment attch, Texture2D &, unsigned level = 0);
 
-	void attach(FrameAttachment attch, Texture2DMultisample &tex);
-	void attach(FrameAttachment attch, Texture3D &tex, unsigned layer, unsigned level = 0);
-	void attach(FrameAttachment attch, TextureCube &tex, TextureCubeFace face, unsigned level = 0);
-	void attach_layered(FrameAttachment attch, Texture3D &tex, unsigned level = 0);
-	void attach_layered(FrameAttachment attch, TextureCube &tex, unsigned level = 0);
+	/** Attaches a multisample texture to the framebuffer.  The texture must
+	have a sample count matching the frame format.  A resolve attachment may
+	be given as well and used to resolve the multisample image into a single
+	value per texel. */
+	void attach(FrameAttachment attch, Texture2DMultisample &, Texture2D *);
+
+	/** Attaches a single layer from a 3-dimensional texture to the
+	framebuffer. */
+	void attach(FrameAttachment attch, Texture3D &, unsigned layer, unsigned level = 0);
+
+	void attach(FrameAttachment attch, TextureCube &, TextureCubeFace face, unsigned level = 0);
+
+	/** Attaches a layered texture to the framebuffer.  Shaders can direct
+	output to a particular layer. */
+	void attach_layered(FrameAttachment attch, Texture3D &, unsigned level = 0);
+
+	void attach_layered(FrameAttachment attch, TextureCube &, unsigned level = 0);
 	void detach(FrameAttachment attch);
 
-	void resize(const WindowView &);
+	const Texture *get_attachment(FrameAttachment) const;
+	const Texture *get_attachment(unsigned) const;
+	const Texture *get_resolve_attachment(FrameAttachment) const;
+	const Texture *get_resolve_attachment(unsigned) const;
+	bool has_resolve_attachments() const;
+
+	using FramebufferBackend::is_presentable;
 
 	/** Ensures that the framebuffer is complete, throwing an exception if it
 	isn't. */
@@ -109,8 +129,6 @@ public:
 	void refresh() const { if(dirty) update(); }
 
 	using FramebufferBackend::set_debug_name;
-
-	static Framebuffer &system();
 };