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comparison src/compass.c @ 621:1ad0531e9078

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3.01 release
author heinrichsweikamp
date Sat, 23 Feb 2019 16:51:14 +0100
parents cd986267a5ca
children c40025d8e750
comparison
equal deleted inserted replaced
620:cd986267a5ca 621:1ad0531e9078
71 71
72 //---- Pre-scale both numerator and denominator -------------------------- 72 //---- Pre-scale both numerator and denominator --------------------------
73 while( (((a>>8) | (b>>8)) & 0xC0) == 0 ) 73 while( (((a>>8) | (b>>8)) & 0xC0) == 0 )
74 { 74 {
75 failsafe--; 75 failsafe--;
76 if (failsafe==0) break; 76 if (failsafe==0) break;
77 a <<= 1; 77 a <<= 1;
78 b <<= 1; 78 b <<= 1;
79 } 79 }
80 80
81 //---- Make division trials ---------------------------------------------- 81 //---- Make division trials ----------------------------------------------
174 /// 174 ///
175 175
176 void sincos(PARAMETER Int16 x, PARAMETER Int16 y, Int16* sin, Int16* cos) 176 void sincos(PARAMETER Int16 x, PARAMETER Int16 y, Int16* sin, Int16* cos)
177 { 177 {
178 OVERLAY Int16 x2, y2, h2; 178 OVERLAY Int16 x2, y2, h2;
179 OVERLAY char failsafe = 250; 179 OVERLAY char failsafe=250;
180 180
181 //---- Fold into one quadant --------------------------------------------- 181 //---- Fold into one quadant ---------------------------------------------
182 OVERLAY char neg = 0; 182 OVERLAY char neg = 0;
183 if( x < 0 ) 183 if( x < 0 )
184 { 184 {
185 neg |= 1; 185 neg |= 1;
188 if( y < 0 ) 188 if( y < 0 )
189 { 189 {
190 neg |= 2; 190 neg |= 2;
191 y = -y; 191 y = -y;
192 } 192 }
193 193
194 //---- Pre-scale both numerator and denominator ---------------------- 194 //---- Pre-scale both numerator and denominator ----------------------
195 while( (((x>>8) | (y>>8)) & 0xE0) == 0 ) 195 while( (((x>>8) | (y>>8)) & 0xE0) == 0 )
196 { 196 {
197 failsafe--; 197 failsafe--;
198 if (failsafe == 0) break; 198 if (failsafe==0) break;
199 x <<= 1; 199 x <<= 1;
200 y <<= 1; 200 y <<= 1;
201 } 201 }
202 202
203 //---- Uses trig() to do the stuff one on quadrant ------------------- 203 //---- Uses trig() to do the stuff one on quadrant -------------------