reactos/lib/3rdparty/freetype/src/tools/test_trig.c

   1 #include <ft2build.h>
   2 #include FT_FREETYPE_H
   3 #include FT_TRIGONOMETRY_H
   4
   5 #include <math.h>
   6 #include <stdio.h>
   7
   8 #define  PI   3.14159265358979323846
   9 #define  SPI  (PI/FT_ANGLE_PI)
  10
  11 /* the precision in 16.16 fixed-point checks. Expect between 2 and 5 */
  12 /* noise LSB bits during operations, due to rounding errors..        */
  13 #define  THRESHOLD  64
  14
  15   static  error = 0;
  16
  17   static void
  18   test_cos( void )
  19   {
  20     int  i;
  21
  22
  23     for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 )
  24     {
  25       FT_Fixed  f1, f2;
  26       double    d2;
  27
  28
  29       f1 = FT_Cos(i);
  30       d2 = cos( i*SPI );
  31       f2 = (FT_Fixed)(d2*65536.0);
  32
  33       if ( abs( f2-f1 ) > THRESHOLD )
  34       {
  35         error = 1;
  36         printf( "FT_Cos[%3d] = %.7f  cos[%3d] = %.7f\n",
  37                 (i >> 16), f1/65536.0, (i >> 16), d2 );
  38       }
  39     }
  40   }
  41
  42
  43   static void
  44   test_sin( void )
  45   {
  46     int  i;
  47
  48
  49     for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 )
  50     {
  51       FT_Fixed  f1, f2;
  52       double    d2;
  53
  54
  55       f1 = FT_Sin(i);
  56       d2 = sin( i*SPI );
  57       f2 = (FT_Fixed)(d2*65536.0);
  58
  59       if ( abs( f2-f1 ) > THRESHOLD )
  60       {
  61         error = 1;
  62         printf( "FT_Sin[%3d] = %.7f  sin[%3d] = %.7f\n",
  63                 (i >> 16), f1/65536.0, (i >> 16), d2 );
  64       }
  65     }
  66   }
  67
  68
  69   static void
  70   test_tan( void )
  71   {
  72     int  i;
  73
  74
  75     for ( i = 0; i < FT_ANGLE_PI2-0x2000000; i += 0x10000 )
  76     {
  77       FT_Fixed  f1, f2;
  78       double    d2;
  79
  80
  81       f1 = FT_Tan(i);
  82       d2 = tan( i*SPI );
  83       f2 = (FT_Fixed)(d2*65536.0);
  84
  85       if ( abs( f2-f1 ) > THRESHOLD )
  86       {
  87         error = 1;
  88         printf( "FT_Tan[%3d] = %.7f  tan[%3d] = %.7f\n",
  89                 (i >> 16), f1/65536.0, (i >> 16), d2 );
  90       }
  91     }
  92   }
  93
  94
  95   static void
  96   test_atan2( void )
  97   {
  98     int  i;
  99
 100
 101     for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 )
 102     {
 103       FT_Fixed  c2, s2;
 104       double    l, a, c1, s1;
 105       int       j;
 106
 107
 108       l  = 5.0;
 109       a  = i*SPI;
 110
 111       c1 = l * cos(a);
 112       s1 = l * sin(a);
 113
 114       c2 = (FT_Fixed)(c1*65536.0);
 115       s2 = (FT_Fixed)(s1*65536.0);
 116
 117       j  = FT_Atan2( c2, s2 );
 118       if ( j < 0 )
 119         j += FT_ANGLE_2PI;
 120
 121       if ( abs( i - j ) > 1 )
 122       {
 123         printf( "FT_Atan2( %.7f, %.7f ) = %.5f, atan = %.5f\n",
 124                 c2/65536.0, s2/65536.0, j/65536.0, i/65536.0 );
 125       }
 126     }
 127   }
 128
 129
 130   static void
 131   test_unit( void )
 132   {
 133     int  i;
 134
 135
 136     for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 )
 137     {
 138       FT_Vector  v;
 139       double     a, c1, s1;
 140       FT_Fixed   c2, s2;
 141
 142
 143       FT_Vector_Unit( &v, i );
 144       a  = ( i*SPI );
 145       c1 = cos(a);
 146       s1 = sin(a);
 147       c2 = (FT_Fixed)(c1*65536.0);
 148       s2 = (FT_Fixed)(s1*65536.0);
 149
 150       if ( abs( v.x-c2 ) > THRESHOLD ||
 151            abs( v.y-s2 ) > THRESHOLD )
 152       {
 153         error = 1;
 154         printf( "FT_Vector_Unit[%3d] = ( %.7f, %.7f )  vec = ( %.7f, %.7f )\n",
 155                 (i >> 16),
 156                 v.x/65536.0, v.y/65536.0,
 157                 c1, s1 );
 158       }
 159     }
 160   }
 161
 162
 163   static void
 164   test_length( void )
 165   {
 166     int  i;
 167
 168
 169     for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 )
 170     {
 171       FT_Vector  v;
 172       FT_Fixed   l, l2;
 173
 174
 175       l   = (FT_Fixed)(500.0*65536.0);
 176       v.x = (FT_Fixed)( l * cos( i*SPI ) );
 177       v.y = (FT_Fixed)( l * sin( i*SPI ) );
 178       l2  = FT_Vector_Length( &v );
 179
 180       if ( abs( l2-l ) > THRESHOLD )
 181       {
 182         error = 1;
 183         printf( "FT_Length( %.7f, %.7f ) = %.5f, length = %.5f\n",
 184                 v.x/65536.0, v.y/65536.0, l2/65536.0, l/65536.0 );
 185       }
 186     }
 187   }
 188
 189
 190   static void
 191   test_rotate( void )
 192   {
 193     int  rotate;
 194
 195
 196     for ( rotate = 0; rotate < FT_ANGLE_2PI; rotate += 0x10000 )
 197     {
 198       double  ra, cra, sra;
 199       int     i;
 200
 201
 202       ra  = rotate*SPI;
 203       cra = cos( ra );
 204       sra = sin( ra );
 205
 206       for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 )
 207       {
 208         FT_Fixed   c2, s2, c4, s4;
 209         FT_Vector  v;
 210         double     l, a, c1, s1, c3, s3;
 211
 212
 213         l  = 500.0;
 214         a  = i*SPI;
 215
 216         c1 = l * cos(a);
 217         s1 = l * sin(a);
 218
 219         v.x = c2 = (FT_Fixed)(c1*65536.0);
 220         v.y = s2 = (FT_Fixed)(s1*65536.0);
 221
 222         FT_Vector_Rotate( &v, rotate );
 223
 224         c3 = c1 * cra - s1 * sra;
 225         s3 = c1 * sra + s1 * cra;
 226
 227         c4 = (FT_Fixed)(c3*65536.0);
 228         s4 = (FT_Fixed)(s3*65536.0);
 229
 230         if ( abs( c4 - v.x ) > THRESHOLD ||
 231              abs( s4 - v.y ) > THRESHOLD )
 232         {
 233           error = 1;
 234           printf( "FT_Rotate( (%.7f,%.7f), %.5f ) = ( %.7f, %.7f ), rot = ( %.7f, %.7f )\n",
 235                   c1, s1, ra,
 236                   c2/65536.0, s2/65536.0,
 237                   c4/65536.0, s4/65536.0 );
 238         }
 239       }
 240     }
 241   }
 242
 243
 244   int main( void )
 245   {
 246     test_cos();
 247     test_sin();
 248     test_tan();
 249     test_atan2();
 250     test_unit();
 251     test_length();
 252     test_rotate();
 253
 254     if (!error)
 255       printf( "trigonometry test ok !\n" );
 256
 257     return !error;
 258   }