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Fixing a rare bug when parsing floating-point numbers in exponent for…
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…m. Thanks to zhao lei to point it out.

git-svn-id: https://assimp.svn.sourceforge.net/svnroot/assimp/trunk@388 67173fc5-114c-0410-ac8e-9d2fd5bffc1f
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aramis_acg committed Apr 15, 2009
1 parent f0ca5b8 commit acdbf77
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Showing 4 changed files with 72 additions and 67 deletions.
5 changes: 4 additions & 1 deletion CREDITS
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Original file line number Diff line number Diff line change
Expand Up @@ -13,7 +13,7 @@ Thanks for your help!
Configuration-Interface, AssImp-Viewer (Win32), Website (Admin and Design), admin.

-Thomas Schulze,
X-, Collda-, BVH-Loader, Postprocessing framework. Data structure & Interface design, documentation.
X-, Collada-, BVH-Loader, Postprocessing framework. Data structure & Interface design, documentation.

-R.Schmidt,
Linux build, eclipse support.
Expand Down Expand Up @@ -58,3 +58,6 @@ The GUY who performed some of the CSM mocaps.

- Andy Maloney
Contributed fixes for the documentation and the doxygen markup

- Zhao Lei
Contributed several bugfixes fixing memory leaks and improving float parsing
64 changes: 31 additions & 33 deletions code/fast_atof.h
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Expand Up @@ -41,7 +41,7 @@ const float fast_atof_table[16] = { // we write [16] here instead of [] to work


// ------------------------------------------------------------------------------------
// convert a string in decimal format to a number
// Convert a string in decimal format to a number
// ------------------------------------------------------------------------------------
inline unsigned int strtol10( const char* in, const char** out=0)
{
Expand All @@ -60,7 +60,7 @@ inline unsigned int strtol10( const char* in, const char** out=0)
}

// ------------------------------------------------------------------------------------
// convert a string in octal format to a number
// Convert a string in octal format to a number
// ------------------------------------------------------------------------------------
inline unsigned int strtol8( const char* in, const char** out=0)
{
Expand All @@ -79,7 +79,7 @@ inline unsigned int strtol8( const char* in, const char** out=0)
}

// ------------------------------------------------------------------------------------
// convert a string in hex format to a number
// Convert a string in hex format to a number
// ------------------------------------------------------------------------------------
inline unsigned int strtol16( const char* in, const char** out=0)
{
Expand Down Expand Up @@ -165,8 +165,8 @@ inline unsigned int strtol_cppstyle( const char* in, const char** out=0)
}

// ------------------------------------------------------------------------------------
// Special version of the function, providing higher accuracy and security
// It is mainly used bx fast_atof to prevent ugly integer overflows.
// Special version of the function, providing higher accuracy and safety
// It is mainly used by fast_atof to prevent ugly and unwanted integer overflows.
// ------------------------------------------------------------------------------------
inline uint64_t strtol10_64( const char* in, const char** out=0, unsigned int* max_inout=0)
{
Expand All @@ -180,7 +180,7 @@ inline uint64_t strtol10_64( const char* in, const char** out=0, unsigned int* m

const uint64_t new_value = ( value * 10 ) + ( *in - '0' );

if (new_value < value) /* numeric overflow */
if (new_value < value) /* numeric overflow, we rely on you */
return value;

value = new_value;
Expand All @@ -191,7 +191,8 @@ inline uint64_t strtol10_64( const char* in, const char** out=0, unsigned int* m
if (max_inout && *max_inout == cur) {

if (out) { /* skip to end */
while (*in >= '0' && *in <= '9')++in;
while (*in >= '0' && *in <= '9')
++in;
*out = in;
}

Expand All @@ -207,6 +208,7 @@ inline uint64_t strtol10_64( const char* in, const char** out=0, unsigned int* m
return value;
}

// Number of relevant decimals for floating-point parsing.
#define AI_FAST_ATOF_RELAVANT_DECIMALS 6

// ------------------------------------------------------------------------------------
Expand All @@ -216,54 +218,49 @@ inline uint64_t strtol10_64( const char* in, const char** out=0, unsigned int* m
// ------------------------------------------------------------------------------------
inline const char* fast_atof_move( const char* c, float& out)
{
bool inv = false;
const char *t;
float f;

if (*c=='-')
{
bool inv = (*c=='-');
if (inv || *c=='+')
++c;
inv = true;
}
else if (*c=='+')++c;

f = (float) strtol10_64 ( c, &c );
if (*c == '.' || (c[0] == ',' && isdigit( c[1])))
if (*c == '.' || (c[0] == ',' && (c[1] >= '0' || c[1] <= '9'))) // allow for commas, too
{
++c;

// NOTE: The original implementation is highly unaccurate here
// The precision of a single IEEE 754 float is not high enough
// everything behind the 6th digit tends to be more inaccurate
// than it would need to be.
// Casting to double seems to solve the problem.
// NOTE: The original implementation is highly unaccurate here. The precision of a single
// IEEE 754 float is not high enough, everything behind the 6th digit tends to be more
// inaccurate than it would need to be. Casting to double seems to solve the problem.
// strtol_64 is used to prevent integer overflow.

// Another fix: this tends to become 0 if we don't limit
// the maximum number of digits
// Another fix: this tends to become 0 for long numbers if we don't limit the maximum
// number of digits to be read. AI_FAST_ATOF_RELAVANT_DECIMALS can be a value between
// 1 and 15.
unsigned int diff = AI_FAST_ATOF_RELAVANT_DECIMALS;
double pl = (double) strtol10_64 ( c, &t, &diff );

pl *= fast_atof_table[diff];

f += (float)pl;

c = t;
}

// FIX: a large 'E' should be allowed, too (occurs in some DXF files)
if (*c == 'e' || *c == 'E')
{
// A major 'E' must be allowed. Necessary for proper reading of some DXF files.
// Thanks to Zhao Lei to point out that this if() must be outside the if (*c == '.' ..)
if (*c == 'e' || *c == 'E')
{
++c;
bool einv = (*c=='-');
if (einv || *c=='+')
++c;
bool einv = (*c=='-');
if (einv)
++c;

float exp = (float)strtol10(c, &c);
if (einv)
exp *= -1.0f;
float exp = (float)strtol10(c, &c);
if (einv)
exp *= -1.0f;

f *= pow(10.0f, exp);
}
f *= pow(10.0f, exp);
}

if (inv)
Expand All @@ -275,6 +272,7 @@ inline const char* fast_atof_move( const char* c, float& out)


// ------------------------------------------------------------------------------------
// The same but more human.
inline float fast_atof(const char* c)
{
float ret;
Expand Down
2 changes: 1 addition & 1 deletion mkutil/revision.h
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@@ -1 +1 @@
#define SVNRevision 377
#define SVNRevision 387
68 changes: 36 additions & 32 deletions workspaces/vc9/assimp.vcproj
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Expand Up @@ -2275,26 +2275,6 @@
RelativePath="..\..\code\BaseProcess.h"
>
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Expand All @@ -2307,14 +2287,6 @@
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>
Expand Down Expand Up @@ -2379,10 +2351,6 @@
RelativePath="..\..\code\StandardShapes.h"
>
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RelativePath="..\..\code\StringComparison.h"
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RelativePath="..\..\code\TargetAnimation.cpp"
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Expand Down Expand Up @@ -3404,6 +3372,42 @@
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Expand Down

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