X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Ftexture3d.h;h=0a03cd5d9e61e1a06d0c41ec3376ca91f4cc0436;hb=ae9abd6be3e556d0a202cc5ab05668da715382c9;hp=8d9566d8ec6c7f82d1112d84024239c2d8b60273;hpb=ceae2a27dfc58310c5bab7e3aa3fedf0fa9a1f49;p=libs%2Fgl.git

diff --git a/source/texture3d.h b/source/texture3d.h
index 8d9566d8..0a03cd5d 100644
--- a/source/texture3d.h
+++ b/source/texture3d.h
@@ -1,10 +1,3 @@
-/* $Id$
-
-This file is part of libmspgl
-Copyright © 2007  Mikko Rasa, Mikkosoft Productions
-Distributed under the LGPL
-*/
-
 #ifndef MSP_GL_TEXTURE3D_H_
 #define MSP_GL_TEXTURE3D_H_
 
@@ -16,6 +9,10 @@ Distributed under the LGPL
 namespace Msp {
 namespace GL {
 
+/**
+Three-dimensional texture.  Consists of an array of texels in the shape of a
+right cuboid.  Texture coordinates have a principal range of [0, 1].
+*/
 class Texture3D: public Texture
 {
 private:
@@ -23,17 +20,46 @@ private:
 	unsigned width;
 	unsigned height;
 	unsigned depth;
-	int border;
+	unsigned allocated;
 
 public:
 	Texture3D();
-	void storage(PixelFormat, unsigned, unsigned, unsigned, int);
-	void image(int, PixelFormat, DataType, const void *);
-	void sub_image(int, int, int, unsigned, unsigned, unsigned, PixelFormat, DataType, const void *);
-	void load_image(const std::string &fn, int dp=-1);
+
+	/** Defines storage structure for the texture.  Must be called before an
+	image can be uploaded.  Once storage is defined, it can't be changed. */
+	void storage(PixelFormat fmt, unsigned wd, unsigned ht, unsigned dp);
+
+	/** Allocates storage for the texture.  The contents are initially
+	undefined.  If storage has already been allocated, does nothing. */
+	void allocate(unsigned level);
+	
+	/** Uploads an image to the texture.  Storage must be defined beforehand.
+	The image data must have dimensions and format compatible with the defined
+	storage. */
+	void image(unsigned level, PixelFormat fmt, DataType type, const void *data);
+
+	/** Updates a cuboid-shaped region of the texture.  Storage must be defined
+	and allocated beforehand.  The update region must be fully inside the
+	texture. */
+	void sub_image(unsigned level,
+		int x, int y, int z, unsigned wd, unsigned ht, unsigned dp,
+		PixelFormat fmt, DataType type, const void *data);
+
+	/** Loads an image from a file and uploads it to the texture.  If storage
+	has not been defined, it will be set to match the loaded image.  To
+	construct a three-dimensional texture from a two-dimensional image, the
+	image is interpreted as an array of consecutive images.  If dp is -1, the
+	texture's width and height are equal.  If dp is -2, the texture's height and
+	depth are equal.  Otherwise, dp must be positive and determines the
+	texture's depth.  In all cases, the image's height must equal the texture's
+	height times its depth. */
+	void load_image(const std::string &fn, int dp = -1);
+
 	unsigned get_width() const { return width; }
 	unsigned get_height() const { return height; }
 	unsigned get_depth() const { return depth; }
+private:
+	void get_level_size(unsigned, unsigned &, unsigned &, unsigned &);
 };
 
 } // namespace GL