mirror of
https://github.com/PixarAnimationStudios/OpenSubdiv
synced 2024-11-23 12:10:08 +00:00
ee061291b7
All kernels take offset/length/stride to apply subdivision partially in each vertex elements. Also the offset can be used for client-based VBO aggregation, without modifying index buffers. This is useful for topology sharing, in conjunction with glDrawElementsBaseVertex etc. However, gregory patch shader fetches vertex buffer via texture buffer, which index should also be offsetted too. Although gl_BaseVertexARB extension should be able to do that job, it's a relatively new extension. So we use OsdBaseVertex() call to mitigate the compatibility issue as clients can provide it in their way at least for the time being.
79 lines
2.6 KiB
C++
79 lines
2.6 KiB
C++
//
|
|
// Copyright 2013 Pixar
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "Apache License")
|
|
// with the following modification; you may not use this file except in
|
|
// compliance with the Apache License and the following modification to it:
|
|
// Section 6. Trademarks. is deleted and replaced with:
|
|
//
|
|
// 6. Trademarks. This License does not grant permission to use the trade
|
|
// names, trademarks, service marks, or product names of the Licensor
|
|
// and its affiliates, except as required to comply with Section 4(c) of
|
|
// the License and to reproduce the content of the NOTICE file.
|
|
//
|
|
// You may obtain a copy of the Apache License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the Apache License with the above modification is
|
|
// distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
|
|
// KIND, either express or implied. See the Apache License for the specific
|
|
// language governing permissions and limitations under the Apache License.
|
|
//
|
|
|
|
#ifndef OSD_CPU_VERTEX_DESCRIPTOR_H
|
|
#define OSD_CPU_VERTEX_DESCRIPTOR_H
|
|
|
|
#include "../version.h"
|
|
#include <string.h>
|
|
|
|
namespace OpenSubdiv {
|
|
namespace OPENSUBDIV_VERSION {
|
|
|
|
/// \brief Describes vertex elements in interleaved data buffers
|
|
struct OsdVertexBufferDescriptor {
|
|
|
|
/// Default Constructor
|
|
OsdVertexBufferDescriptor() : offset(0), length(0), stride(0) { }
|
|
|
|
/// Constructor
|
|
OsdVertexBufferDescriptor(int o, int l, int s) : offset(o), length(l), stride(s) { }
|
|
|
|
/// True if the descriptor values are internally consistent
|
|
bool IsValid() const {
|
|
return ((length>0) and (offset<stride) and (length<=stride-offset));
|
|
}
|
|
|
|
/// True if the 'other' descriptor can be used as a destination for
|
|
/// data evaluations.
|
|
bool CanEval( OsdVertexBufferDescriptor const & other ) const {
|
|
return (IsValid() and
|
|
other.IsValid() and
|
|
(length==other.length));
|
|
}
|
|
|
|
/// Resets the descriptor to default
|
|
void Reset() {
|
|
offset = length = stride = 0;
|
|
}
|
|
|
|
/// True if the descriptors are identical
|
|
bool operator == ( OsdVertexBufferDescriptor const other ) const {
|
|
return (offset == other.offset and
|
|
length == other.length and
|
|
stride == other.stride);
|
|
}
|
|
|
|
int offset; // offset to desired element data
|
|
int length; // number or length of the data
|
|
int stride; // stride to the next element
|
|
};
|
|
|
|
} // end namespace OPENSUBDIV_VERSION
|
|
using namespace OPENSUBDIV_VERSION;
|
|
|
|
} // end namespace OpenSubdiv
|
|
|
|
#endif /* OSD_CPU_VERTEX_DESCRIPTRO_H */
|