summaryrefslogtreecommitdiff
path: root/thirdparty/etcpak/Math.hpp
diff options
context:
space:
mode:
Diffstat (limited to 'thirdparty/etcpak/Math.hpp')
-rw-r--r--thirdparty/etcpak/Math.hpp92
1 files changed, 92 insertions, 0 deletions
diff --git a/thirdparty/etcpak/Math.hpp b/thirdparty/etcpak/Math.hpp
new file mode 100644
index 0000000000..994e1ac4ea
--- /dev/null
+++ b/thirdparty/etcpak/Math.hpp
@@ -0,0 +1,92 @@
+#ifndef __DARKRL__MATH_HPP__
+#define __DARKRL__MATH_HPP__
+
+#include <algorithm>
+#include <cmath>
+#include <stdint.h>
+
+#include "ForceInline.hpp"
+
+template<typename T>
+static etcpak_force_inline T AlignPOT( T val )
+{
+ if( val == 0 ) return 1;
+ val--;
+ for( unsigned int i=1; i<sizeof( T ) * 8; i <<= 1 )
+ {
+ val |= val >> i;
+ }
+ return val + 1;
+}
+
+static etcpak_force_inline int CountSetBits( uint32_t val )
+{
+ val -= ( val >> 1 ) & 0x55555555;
+ val = ( ( val >> 2 ) & 0x33333333 ) + ( val & 0x33333333 );
+ val = ( ( val >> 4 ) + val ) & 0x0f0f0f0f;
+ val += val >> 8;
+ val += val >> 16;
+ return val & 0x0000003f;
+}
+
+static etcpak_force_inline int CountLeadingZeros( uint32_t val )
+{
+ val |= val >> 1;
+ val |= val >> 2;
+ val |= val >> 4;
+ val |= val >> 8;
+ val |= val >> 16;
+ return 32 - CountSetBits( val );
+}
+
+static etcpak_force_inline float sRGB2linear( float v )
+{
+ const float a = 0.055f;
+ if( v <= 0.04045f )
+ {
+ return v / 12.92f;
+ }
+ else
+ {
+ return pow( ( v + a ) / ( 1 + a ), 2.4f );
+ }
+}
+
+static etcpak_force_inline float linear2sRGB( float v )
+{
+ const float a = 0.055f;
+ if( v <= 0.0031308f )
+ {
+ return 12.92f * v;
+ }
+ else
+ {
+ return ( 1 + a ) * pow( v, 1/2.4f ) - a;
+ }
+}
+
+template<class T>
+static etcpak_force_inline T SmoothStep( T x )
+{
+ return x*x*(3-2*x);
+}
+
+static etcpak_force_inline uint8_t clampu8( int32_t val )
+{
+ if( ( val & ~0xFF ) == 0 ) return val;
+ return ( ( ~val ) >> 31 ) & 0xFF;
+}
+
+template<class T>
+static etcpak_force_inline T sq( T val )
+{
+ return val * val;
+}
+
+static etcpak_force_inline int mul8bit( int a, int b )
+{
+ int t = a*b + 128;
+ return ( t + ( t >> 8 ) ) >> 8;
+}
+
+#endif