diff options
| author | Kenneth Russel <[email protected]> | 2006-01-22 16:50:38 +0000 |
|---|---|---|
| committer | Kenneth Russel <[email protected]> | 2006-01-22 16:50:38 +0000 |
| commit | c4b0494f729d9fb1ecf69e399c3a8d683f772d05 (patch) | |
| tree | 49cca7c93137a364c8da7c4ea7fb961304d8fe7f /make | |
| parent | 72acc211539803f1ef57d4331938afb48600398e (diff) | |
Fixed Issue 179: Add documentation on importance of byte ordering
Added text to the spec overview regarding setting byte order of
newly-allocated ByteBuffers to native order.
git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/svn-server-sync/jogl/trunk@558 232f8b59-042b-4e1e-8c03-345bb8c30851
Diffstat (limited to 'make')
| -rw-r--r-- | make/spec-overview.html | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/make/spec-overview.html b/make/spec-overview.html index 36b92e2cc..fdeb972c2 100644 --- a/make/spec-overview.html +++ b/make/spec-overview.html @@ -135,6 +135,20 @@ all Buffer types.<br> all non-direct Buffers. Direct and non-direct buffers should never be mixed within an API call by an application.<br> +<h4>Byte ordering of Buffers</h4> + When allocating a New I/O Buffer (in particular, a direct ByteBuffer) +to be passed to the APIs in these packages, it is essential to set the +<em>byte ordering</em> of the newly-allocated ByteBuffer to the +<em>native</em> byte ordering of the platform: +e.g. <code>ByteBuffer.allocateDirect(...).order(ByteOrder.nativeOrder());</code>. +The byte order of the ByteBuffer indicates how multi-byte values such +as int and float are stored in the Buffer either using methods like +putInt and putFloat or views such as IntBuffer or FloatBuffer. The +Java bindings perform no conversion or byte swapping on the outgoing +data to OpenGL, and the native OpenGL implementation expects data in +the host CPU's byte order, so it is essential to always match the byte +order of the underlying platform when filling Buffers with data. <br> + <h4>Auto-slicing of Buffers</h4> When a Buffer object is passed to an OpenGL function binding, the actual pointer argument that is passed down to the OpenGL C implementation is equal |