Package com.jogamp.gluegen

JogAmp GlueGen Code Generator

GlueGen Data Type Mapping

Gluegen has build-in types (terminal symbols) for:

type java bits native bits type signed origin
x32 x64
void 0 0 0 void void ANSI-C
char 8 8 8 integerany ANSI-C
short 16 16 16 integerany ANSI-C
int 32 32 32 integerany ANSI-C
long 64 32 321 integerany ANSI-C - Windows
long 64 32 64 integerany ANSI-C - Unix
float 32 32 32 float signed ANSI-C
double 64 64 64 double signed ANSI-C
__int32 32 32 32 integerany windows
__int64 64 64 64 integerany windows
int8_t 8 8 8 integersigned stdint.h
uint8_t 8 8 8 integerunsigned stdint.h
int16_t 16 16 16 integersigned stdint.h
uint16_t 16 16 16 integerunsigned stdint.h
int32_t 32 32 32 integersigned stdint.h
uint32_t 32 32 32 integerunsigned stdint.h
int64_t 64 64 64 integersigned stdint.h
uint64_t 64 64 64 integerunsigned stdint.h
intptr_t 64 32 64 integersigned stdint.h
uintptr_t 64 32 64 integerunsigned stdint.h
ptrdiff_t 64 32 64 integersigned stddef.h
size_t 64 32 64 integerunsigned stddef.h
wchar_t 32 32 32 integersigned stddef.h

Warning: Try to avoid unspecified bit sized types, especially long, since it differs on Unix and Windows!
Notes:

  1. Type long will result in broken code on Windows, since we don't differentiate the OS and it's bit size is ambiguous.
  2. Anonymous void-pointer void* are mapped to NIO Buffer.
  3. Pointers to pointer-size types like intptr_t*, uintptr_t*, ptrdiff_t* and size_t* are mapped to PointerBuffer, to reflect the architecture depending storage size.

GlueGen Internal Alignment for Compound Data

In general, depending on CPU and it's configuration (OS), alignment is set up for each type (char, short, int, long, ..).

Compounds (structures) are aligned naturally, i.e. their inner components are aligned
and are itself aligned to it's largest element.

See:
Simple alignment arithmetic
Modulo operation, where the 2nd handles the case offset == alignment:
padding = ( alignment - ( offset % alignment ) ) % alignment ;
aligned_offset = offset + padding ;
Optimization utilizing alignment as a multiple of 2 -> x % 2n == x & ( 2n - 1 )
remainder = offset & ( alignment - 1 ) ;
padding = ( remainder > 0 ) ? alignment - remainder : 0 ;
aligned_offset = offset + padding ;
Without branching, using the 2nd modulo operation for the case offset == alignment:
padding = ( alignment - ( offset & ( alignment - 1 ) ) ) & ( alignment - 1 ) ;
aligned_offset = offset + padding ;
See com.jogamp.gluegen.cgram.types.SizeThunk.align(..).
Type Size & Alignment for x86, x86_64, armv6l-32bit-eabi and Window(mingw/mingw64)
Runtime query is implemented as follows:
   typedef struct {
     char   fill;  // nibble one byte
                   // padding to align s1: padding_0 
     type_t s1;    // 
   } test_struct_type_t;
  
             padding_0 = sizeof(test_struct_type_t) - sizeof(type_t) - sizeof(char) ;
   alignmentOf(type_t) = sizeof(test_struct_type_t) - sizeof(type_t) ;
  
type 32 bits64 bits
sizealignmentsizealignment
char 1 1 1 1
short 2 2 2 2
int 4 4 4 4
float 4 4 4 4
long 4 4 8,4 8,4
pointer 4 4 8 8
long long 8 4,8+ 8 8
double 8 4,8+ 8 8
long double12,8+,16- 4,8+,16- 16 16

Linux, Darwin
+armv7l-eabi
- MacOsX-32bit-gcc4
Windows

GlueGen Platform Header Files

GlueGen provides convenient platform headers,
which can be included in your C header files for native compilation and GlueGen code generation.

Example:
   #include <gluegen_stdint.h>
   #include <gluegen_stddef.h>
 
   uint64_t test64;
   size_t size1;
   ptrdiff_t ptr1;
  

To compile this file you have to include the following folder to your compilers system includes, ie -I:
    gluegen/make/stub_includes/platform
  

To generate code for this file you have to include the following folder to your GlueGen includeRefid element:
    gluegen/make/stub_includes/gluegen
  

GlueGen Pre-Defined Macros

To identity a GlueGen code generation run, GlueGen defines the following macros:
     #define __GLUEGEN__ 2