Christian, this is a plugin free project for me. :-)
Norman Wrote:
>> RedBlackRedRampEvaluate(ByRef info As MemoryBlock, inValue As
>> MemoryBlock, ByRef outValue As MemoryBlock)
> This should just be Ptr. Byref is not required.
> RedBlackRedRampEvaluate( info As Ptr, inValue As Ptr, outValue As Ptr)
Charles Wrote:
> Probably you should declare all three parameters to be of type
> MemoryBlock.
> Sub RedBlackRedRampEvaluate(info as MemoryBlock, inValue as
> MemoryBlock, outValue as MemoryBlock)
These two replies indicate my fundamental question. It appears that there is
no *correct* answer, other than to try each out and see what works. :-)
Norman Wrote:
> The caller puts them on the stack (usually) according to that
> lannguages calling conventions (which appear to be C)
> They should be set already when you are called assuming there's
> nothing funky about calling conventions.
I'm still confused. Let's say you have a Routine and a call,
// Method
MyTestRoutine(aPtr As MemoryBlock)
// a Call
Dim temp As New MemoryBlock(12)
temp.Ptr(4) = AddressOf MyTestRoutine
How does Rb find the parameter aPtr in MyTestRoutine? By name?
> It means the PTR cannot be changed but the thing the Ptr is pointing
> at can be. Just don't try and change the Ptr. You can alter the data the
pointer points to though.
Ah, that's it. thank you.
Charles Wrote:
> In this case, you need to examine the documentation for
> CGFunctionEvaluateCallback. The second and third parameters are
> arrays of type float whose sizes you supplied to CGFunctionCreate.
> Probably you should declare all three parameters to be of type
> MemoryBlock.
I try to only post here without many many times reading the docs, as is the
case here. The docs at this point are not getting me what I am looking to
do, yet.
> You might want to post your code for CGFunctionCreate; that has to be
> done correctly for the callbacks to work.
Right, I understand the connection to this. I have at this point,
// info ptr variable
infoPtr.UInt32(0) = CGColorSpaceGetNumberOfComponents(aClrSpace) + 1 // 4
// Dimension of aDomain is 1 and dimension of aRange is 4.
aFunctionRef = CGFunctionCreate(infoPtr, 1, aDomain, 4, aRange, aCallBack)
aDomain and aRange are MemoryBlock with floats (singles) that correspond
(sized and assigned) to 1 and 4 parameters at 4 bytes each. aCallback is a
MemoryBlock class with its evaluate pointer set to,
aCallBack.Ptr(4) = AddressOf MyRedBlackRedRampEvaluate
The Callback structure is,
struct CGFunctionCallbacks
{
unsigned int version;
CGFunctionEvaluateCallback evaluate;
CGFunctionReleaseInfoCallback releaseInfo
};
I appreciate your replies. --Thomas C.
_______________________________________________
Unsubscribe or switch delivery mode:
<http://www.realsoftware.com/support/listmanager/>
Search the archives:
<http://support.realsoftware.com/listarchives/lists.html>
