diff options
Diffstat (limited to 'src/tools/test_trig.c')
| -rw-r--r-- | src/tools/test_trig.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/src/tools/test_trig.c b/src/tools/test_trig.c new file mode 100644 index 0000000..8c8a544 --- /dev/null +++ b/src/tools/test_trig.c @@ -0,0 +1,236 @@ +#include <ft2build.h> +#include FT_FREETYPE_H +#include FT_TRIGONOMETRY_H + +#include <math.h> +#include <stdio.h> + +#define PI 3.14159265358979323846 +#define SPI (PI/FT_ANGLE_PI) + +/* the precision in 16.16 fixed float points of the checks. Expect */ +/* between 2 and 5 noise LSB bits during operations, due to */ +/* rounding errors.. */ +#define THRESHOLD 64 + + static error = 0; + + static void + test_cos( void ) + { + FT_Fixed f1, f2; + double d1, d2; + int i; + + for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 ) + { + f1 = FT_Cos(i); + d1 = f1/65536.0; + d2 = cos( i*SPI ); + f2 = (FT_Fixed)(d2*65536.0); + + if ( abs( f2-f1 ) > THRESHOLD ) + { + error = 1; + printf( "FT_Cos[%3d] = %.7f cos[%3d] = %.7f\n", + (i >> 16), f1/65536.0, (i >> 16), d2 ); + } + } + } + + + + static void + test_sin( void ) + { + FT_Fixed f1, f2; + double d1, d2; + int i; + + for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 ) + { + f1 = FT_Sin(i); + d1 = f1/65536.0; + d2 = sin( i*SPI ); + f2 = (FT_Fixed)(d2*65536.0); + + if ( abs( f2-f1 ) > THRESHOLD ) + { + error = 1; + printf( "FT_Sin[%3d] = %.7f sin[%3d] = %.7f\n", + (i >> 16), f1/65536.0, (i >> 16), d2 ); + } + } + } + + + static void + test_tan( void ) + { + FT_Fixed f1, f2; + double d1, d2; + int i; + + for ( i = 0; i < FT_ANGLE_PI2-0x2000000; i += 0x10000 ) + { + f1 = FT_Tan(i); + d1 = f1/65536.0; + d2 = tan( i*SPI ); + f2 = (FT_Fixed)(d2*65536.0); + + if ( abs( f2-f1 ) > THRESHOLD ) + { + error = 1; + printf( "FT_Tan[%3d] = %.7f tan[%3d] = %.7f\n", + (i >> 16), f1/65536.0, (i >> 16), d2 ); + } + } + } + + + static void + test_atan2( void ) + { + FT_Fixed c2, s2; + double l, a, c1, s1; + int i, j; + + for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 ) + { + l = 5.0; + a = i*SPI; + + c1 = l * cos(a); + s1 = l * sin(a); + + c2 = (FT_Fixed)(c1*65536.0); + s2 = (FT_Fixed)(s1*65536.0); + + j = FT_Atan2( c2, s2 ); + if ( j < 0 ) + j += FT_ANGLE_2PI; + + if ( abs( i - j ) > 1 ) + { + printf( "FT_Atan2( %.7f, %.7f ) = %.5f, atan = %.5f\n", + c2/65536.0, s2/65536.0, j/65536.0, i/65536.0 ); + } + } + } + + static void + test_unit( void ) + { + FT_Vector v; + double a, c1, s1; + FT_Fixed c2, s2; + int i; + + for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 ) + { + FT_Vector_Unit( &v, i ); + a = ( i*SPI ); + c1 = cos(a); + s1 = sin(a); + c2 = (FT_Fixed)(c1*65536.0); + s2 = (FT_Fixed)(s1*65536.0); + + if ( abs( v.x-c2 ) > THRESHOLD || + abs( v.y-s2 ) > THRESHOLD ) + { + error = 1; + printf( "FT_Vector_Unit[%3d] = ( %.7f, %.7f ) vec = ( %.7f, %.7f )\n", + (i >> 16), + v.x/65536.0, v.y/65536.0, + c1, s1 ); + } + } + } + + + static void + test_length( void ) + { + FT_Vector v; + FT_Fixed l, l2; + int i; + + for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 ) + { + l = (FT_Fixed)(500.0*65536.0); + v.x = (FT_Fixed)( l * cos( i*SPI ) ); + v.y = (FT_Fixed)( l * sin( i*SPI ) ); + l2 = FT_Vector_Length( &v ); + + if ( abs( l2-l ) > THRESHOLD ) + { + error = 1; + printf( "FT_Length( %.7f, %.7f ) = %.5f, length = %.5f\n", + v.x/65536.0, v.y/65536.0, l2/65536.0, l/65536.0 ); + } + } + } + + + static void + test_rotate( void ) + { + FT_Fixed c2, s2, c4, s4; + FT_Vector v; + double l, ra, a, c1, s1, cra, sra, c3, s3; + int i, j, rotate; + + for ( rotate = 0; rotate < FT_ANGLE_2PI; rotate += 0x10000 ) + { + ra = rotate*SPI; + cra = cos( ra ); + sra = sin( ra ); + + for ( i = 0; i < FT_ANGLE_2PI; i += 0x10000 ) + { + l = 500.0; + a = i*SPI; + + c1 = l * cos(a); + s1 = l * sin(a); + + v.x = c2 = (FT_Fixed)(c1*65536.0); + v.y = s2 = (FT_Fixed)(s1*65536.0); + + FT_Vector_Rotate( &v, rotate ); + + c3 = c1 * cra - s1 * sra; + s3 = c1 * sra + s1 * cra; + + c4 = (FT_Fixed)(c3*65536.0); + s4 = (FT_Fixed)(s3*65536.0); + + if ( abs( c4 - v.x ) > THRESHOLD || + abs( s4 - v.y ) > THRESHOLD ) + { + error = 1; + printf( "FT_Rotate( (%.7f,%.7f), %.5f ) = ( %.7f, %.7f ), rot = ( %.7f, %.7f )\n", + c1, s1, ra, + c2/65536.0, s2/65536.0, + c4/65536.0, s4/65536.0 ); + } + } + } + } + + + int main( void ) + { + test_cos(); + test_sin(); + test_tan(); + test_atan2(); + test_unit(); + test_length(); + test_rotate(); + + if (!error) + printf( "trigonometry test ok !\n" ); + + return !error; + } |