llpatchvertexarray.h
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- /**
- * @file llpatchvertexarray.h
- * @brief description of Surface class
- *
- * $LicenseInfo:firstyear=2001&license=viewergpl$
- *
- * Copyright (c) 2001-2010, Linden Research, Inc.
- *
- * Second Life Viewer Source Code
- * The source code in this file ("Source Code") is provided by Linden Lab
- * to you under the terms of the GNU General Public License, version 2.0
- * ("GPL"), unless you have obtained a separate licensing agreement
- * ("Other License"), formally executed by you and Linden Lab. Terms of
- * the GPL can be found in doc/GPL-license.txt in this distribution, or
- * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
- *
- * There are special exceptions to the terms and conditions of the GPL as
- * it is applied to this Source Code. View the full text of the exception
- * in the file doc/FLOSS-exception.txt in this software distribution, or
- * online at
- * http://secondlifegrid.net/programs/open_source/licensing/flossexception
- *
- * By copying, modifying or distributing this software, you acknowledge
- * that you have read and understood your obligations described above,
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- * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
- * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
- * COMPLETENESS OR PERFORMANCE.
- * $/LicenseInfo$
- */
- #ifndef LL_LLPATCHVERTEXARRAY_H
- #define LL_LLPATCHVERTEXARRAY_H
- // A LLPatchVertexArray is really just a structure of vertex arrays for
- // rendering a "patch" of a certain size.
- //
- // A "patch" is currently a sub-square of a larger square array of data
- // we call a "surface".
- class LLPatchVertexArray
- {
- public:
- LLPatchVertexArray();
- LLPatchVertexArray(U32 surface_width, U32 patch_width, F32 meters_per_grid);
- virtual ~LLPatchVertexArray();
- void create(U32 surface_width, U32 patch_width, F32 meters_per_grid);
- void destroy();
- void init();
- public:
- U32 mSurfaceWidth; // grid points on one side of a LLSurface
- U32 mPatchWidth; // grid points on one side of a LLPatch
- U32 mPatchOrder; // 2^mPatchOrder >= mPatchWidth
- U32 *mRenderLevelp; // Look-up table : render_stride -> render_level
- U32 *mRenderStridep; // Look-up table : render_level -> render_stride
- // We want to be able to render a patch from multiple resolutions.
- // The lowest resolution has two triangles, and the highest has
- // 2*mPatchWidth*mPatchWidth triangles.
- //
- // mPatchWidth is not hard-coded, so we don't know how much memory
- // to allocate to the vertex arrays until it is set. Once it is
- // set, we will calculate how much total memory to allocate for the
- // vertex arrays, and then keep track of their lengths and locations
- // in the memory bank.
- //
- // A Patch has three regions that need vertex arrays: middle, north,
- // and east. For each region there are three items that must be
- // kept track of: data, offset, and length.
- };
- #endif