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glClearBufferData- How to Use It?

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Hello, I need to learn the proper usage for glClearBufferData for an application I'm creating. I've looked at the official documentation... which isn't very descriptive, mainly what I don't understand are the internalformat, format, and type parameters.

void glClearBufferData( GLenum target,
GLenum internalformat,
GLenum format,
GLenum type,
const void * data);

I have a buffer with a target and some data, and all the data are in float form. I want to clear it all out to 0. Question is, how? Which one do I specify that it's in floats? Internalformat? What about the format and type? I just want to clear out all the memory. I know to specify NULL for data... but what about format and type?

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You can look through the http://www.opengl.or...ffer_object.txt document, they got some explanation there:


To fill all or part of an existing buffer object's data store with a
constant value, call
void ClearBufferSubData(enum target,
enum internalformat,
enum format,
enum type,
sizeiptr offset,
sizeiptr size,
const void * data);
with <target> set to the target to which the destination buffer is bound.
<target> must be one of the targets listed in Table 2.8.
<internalformat> must be set to one of the format tokens listed in Table
3.15, "Internal formats for buffer textures". <format> and <type> specify
the format and type of the source data and are interpreted as described in
Section 3.7.2. <offset> set to the offset, measured in basic
machine units, into the buffer object's data store from which to begin
filling, and <size> set to the size, also in basic machine units, of the
range to fill. Both <offset> and <range> must be multiples of the number
of basic machine units per-element for that internal format specified by
<internalformat>, otherwise the error INVALID_VALUE is generated.
<data> is a pointer to an array of between one and four components
containing the data to be used as the source of the constant fill value.
The elements of <data> are converted by the GL into the format specified by
<internalformat> in the manner described in section 2.3.1, and then used to
fill the specified range of the destination buffer. If <data> is NULL, then
the pointer is ignored and the sub-range of the buffer is filled with zeros.
If <offset> or <size> is less than zero, or if <offset> + <size> is
greater than the value of BUFFER_SIZE for the buffer bound to <target>
then the error INVALID_VALUE is generated. The command
An INVALID_OPERATION error is generated if any part of the specified
range of the buffer bound to <target> is currently mapped.
void ClearBufferData(enum target,
enum internalformat,
enum format,
enum type,
const void * data);
is equivalent to calling ClearBufferSubData with <target>,
<internalformat> and <data> as specified, with <offset> set to zero,
and <size> set to the value of BUFFER_SIZE for the buffer bound to
<target>.

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