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<div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="preprocessor">#ifndef __INC_LIB8TION_TRIG_H</span></div>
<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="preprocessor">#define __INC_LIB8TION_TRIG_H</span></div>
<div class="line"><a name="l00003"></a><span class="lineno"> 3</span> </div>
<div class="line"><a name="l00005"></a><span class="lineno"> 5</span> </div>
<div class="line"><a name="l00016"></a><span class="lineno"> 16</span> </div>
<div class="line"><a name="l00017"></a><span class="lineno"> 17</span> <span class="preprocessor">#if defined(__AVR__)</span></div>
<div class="line"><a name="l00018"></a><span class="lineno"> 18</span> <span class="preprocessor">#define sin16 sin16_avr</span></div>
<div class="line"><a name="l00019"></a><span class="lineno"> 19</span> <span class="preprocessor">#else</span></div>
<div class="line"><a name="l00020"></a><span class="lineno"> 20</span> <span class="preprocessor">#define sin16 sin16_C</span></div>
<div class="line"><a name="l00021"></a><span class="lineno"> 21</span> <span class="preprocessor">#endif</span></div>
<div class="line"><a name="l00022"></a><span class="lineno"> 22</span> </div>
<div class="line"><a name="l00030"></a><span class="lineno"><a class="line" href="group___trig.html#ga660ff60bfc5116525e50187de72009fc"> 30</a></span> LIB8STATIC int16_t <a class="code" href="group___trig.html#ga660ff60bfc5116525e50187de72009fc">sin16_avr</a>( uint16_t theta )</div>
<div class="line"><a name="l00031"></a><span class="lineno"> 31</span> {</div>
<div class="line"><a name="l00032"></a><span class="lineno"> 32</span>  <span class="keyword">static</span> <span class="keyword">const</span> uint8_t data[] =</div>
<div class="line"><a name="l00033"></a><span class="lineno"> 33</span>  { 0, 0, 49, 0, 6393%256, 6393/256, 48, 0,</div>
<div class="line"><a name="l00034"></a><span class="lineno"> 34</span>  12539%256, 12539/256, 44, 0, 18204%256, 18204/256, 38, 0,</div>
<div class="line"><a name="l00035"></a><span class="lineno"> 35</span>  23170%256, 23170/256, 31, 0, 27245%256, 27245/256, 23, 0,</div>
<div class="line"><a name="l00036"></a><span class="lineno"> 36</span>  30273%256, 30273/256, 14, 0, 32137%256, 32137/256, 4 <span class="comment">/*,0*/</span> };</div>
<div class="line"><a name="l00037"></a><span class="lineno"> 37</span> </div>
<div class="line"><a name="l00038"></a><span class="lineno"> 38</span>  uint16_t offset = (theta & 0x3FFF);</div>
<div class="line"><a name="l00039"></a><span class="lineno"> 39</span> </div>
<div class="line"><a name="l00040"></a><span class="lineno"> 40</span>  <span class="comment">// AVR doesn't have a multi-bit shift instruction,</span></div>
<div class="line"><a name="l00041"></a><span class="lineno"> 41</span>  <span class="comment">// so if we say "offset >>= 3", gcc makes a tiny loop.</span></div>
<div class="line"><a name="l00042"></a><span class="lineno"> 42</span>  <span class="comment">// Inserting empty volatile statements between each</span></div>
<div class="line"><a name="l00043"></a><span class="lineno"> 43</span>  <span class="comment">// bit shift forces gcc to unroll the loop.</span></div>
<div class="line"><a name="l00044"></a><span class="lineno"> 44</span>  offset >>= 1; <span class="comment">// 0..8191</span></div>
<div class="line"><a name="l00045"></a><span class="lineno"> 45</span>  <span class="keyword">asm</span> <span class="keyword">volatile</span>(<span class="stringliteral">""</span>);</div>
<div class="line"><a name="l00046"></a><span class="lineno"> 46</span>  offset >>= 1; <span class="comment">// 0..4095</span></div>
<div class="line"><a name="l00047"></a><span class="lineno"> 47</span>  <span class="keyword">asm</span> <span class="keyword">volatile</span>(<span class="stringliteral">""</span>);</div>
<div class="line"><a name="l00048"></a><span class="lineno"> 48</span>  offset >>= 1; <span class="comment">// 0..2047</span></div>
<div class="line"><a name="l00049"></a><span class="lineno"> 49</span> </div>
<div class="line"><a name="l00050"></a><span class="lineno"> 50</span>  <span class="keywordflow">if</span>( theta & 0x4000 ) offset = 2047 - offset;</div>
<div class="line"><a name="l00051"></a><span class="lineno"> 51</span> </div>
<div class="line"><a name="l00052"></a><span class="lineno"> 52</span>  uint8_t sectionX4;</div>
<div class="line"><a name="l00053"></a><span class="lineno"> 53</span>  sectionX4 = offset / 256;</div>
<div class="line"><a name="l00054"></a><span class="lineno"> 54</span>  sectionX4 *= 4;</div>
<div class="line"><a name="l00055"></a><span class="lineno"> 55</span> </div>
<div class="line"><a name="l00056"></a><span class="lineno"> 56</span>  uint8_t m;</div>
<div class="line"><a name="l00057"></a><span class="lineno"> 57</span> </div>
<div class="line"><a name="l00058"></a><span class="lineno"> 58</span>  <span class="keyword">union </span>{</div>
<div class="line"><a name="l00059"></a><span class="lineno"> 59</span>  uint16_t b;</div>
<div class="line"><a name="l00060"></a><span class="lineno"> 60</span>  <span class="keyword">struct </span>{</div>
<div class="line"><a name="l00061"></a><span class="lineno"> 61</span>  uint8_t blo;</div>
<div class="line"><a name="l00062"></a><span class="lineno"> 62</span>  uint8_t bhi;</div>
<div class="line"><a name="l00063"></a><span class="lineno"> 63</span>  };</div>
<div class="line"><a name="l00064"></a><span class="lineno"> 64</span>  } u;</div>
<div class="line"><a name="l00065"></a><span class="lineno"> 65</span> </div>
<div class="line"><a name="l00066"></a><span class="lineno"> 66</span>  <span class="comment">//in effect u.b = blo + (256 * bhi);</span></div>
<div class="line"><a name="l00067"></a><span class="lineno"> 67</span>  u.blo = data[ sectionX4 ];</div>
<div class="line"><a name="l00068"></a><span class="lineno"> 68</span>  u.bhi = data[ sectionX4 + 1];</div>
<div class="line"><a name="l00069"></a><span class="lineno"> 69</span>  m = data[ sectionX4 + 2];</div>
<div class="line"><a name="l00070"></a><span class="lineno"> 70</span> </div>
<div class="line"><a name="l00071"></a><span class="lineno"> 71</span>  uint8_t secoffset8 = (uint8_t)(offset) / 2;</div>
<div class="line"><a name="l00072"></a><span class="lineno"> 72</span> </div>
<div class="line"><a name="l00073"></a><span class="lineno"> 73</span>  uint16_t mx = m * secoffset8;</div>
<div class="line"><a name="l00074"></a><span class="lineno"> 74</span> </div>
<div class="line"><a name="l00075"></a><span class="lineno"> 75</span>  int16_t y = mx + u.b;</div>
<div class="line"><a name="l00076"></a><span class="lineno"> 76</span>  <span class="keywordflow">if</span>( theta & 0x8000 ) y = -y;</div>
<div class="line"><a name="l00077"></a><span class="lineno"> 77</span> </div>
<div class="line"><a name="l00078"></a><span class="lineno"> 78</span>  <span class="keywordflow">return</span> y;</div>
<div class="line"><a name="l00079"></a><span class="lineno"> 79</span> }</div>
<div class="line"><a name="l00080"></a><span class="lineno"> 80</span> </div>
<div class="line"><a name="l00088"></a><span class="lineno"><a class="line" href="group___trig.html#ga0890962cb06b267617f4b06d7e9be5eb"> 88</a></span> LIB8STATIC int16_t <a class="code" href="group___trig.html#ga0890962cb06b267617f4b06d7e9be5eb">sin16_C</a>( uint16_t theta )</div>
<div class="line"><a name="l00089"></a><span class="lineno"> 89</span> {</div>
<div class="line"><a name="l00090"></a><span class="lineno"> 90</span>  <span class="keyword">static</span> <span class="keyword">const</span> uint16_t base[] =</div>
<div class="line"><a name="l00091"></a><span class="lineno"> 91</span>  { 0, 6393, 12539, 18204, 23170, 27245, 30273, 32137 };</div>
<div class="line"><a name="l00092"></a><span class="lineno"> 92</span>  <span class="keyword">static</span> <span class="keyword">const</span> uint8_t slope[] =</div>
<div class="line"><a name="l00093"></a><span class="lineno"> 93</span>  { 49, 48, 44, 38, 31, 23, 14, 4 };</div>
<div class="line"><a name="l00094"></a><span class="lineno"> 94</span> </div>
<div class="line"><a name="l00095"></a><span class="lineno"> 95</span>  uint16_t offset = (theta & 0x3FFF) >> 3; <span class="comment">// 0..2047</span></div>
<div class="line"><a name="l00096"></a><span class="lineno"> 96</span>  <span class="keywordflow">if</span>( theta & 0x4000 ) offset = 2047 - offset;</div>
<div class="line"><a name="l00097"></a><span class="lineno"> 97</span> </div>
<div class="line"><a name="l00098"></a><span class="lineno"> 98</span>  uint8_t section = offset / 256; <span class="comment">// 0..7</span></div>
<div class="line"><a name="l00099"></a><span class="lineno"> 99</span>  uint16_t b = base[section];</div>
<div class="line"><a name="l00100"></a><span class="lineno"> 100</span>  uint8_t m = slope[section];</div>
<div class="line"><a name="l00101"></a><span class="lineno"> 101</span> </div>
<div class="line"><a name="l00102"></a><span class="lineno"> 102</span>  uint8_t secoffset8 = (uint8_t)(offset) / 2;</div>
<div class="line"><a name="l00103"></a><span class="lineno"> 103</span> </div>
<div class="line"><a name="l00104"></a><span class="lineno"> 104</span>  uint16_t mx = m * secoffset8;</div>
<div class="line"><a name="l00105"></a><span class="lineno"> 105</span>  int16_t y = mx + b;</div>
<div class="line"><a name="l00106"></a><span class="lineno"> 106</span> </div>
<div class="line"><a name="l00107"></a><span class="lineno"> 107</span>  <span class="keywordflow">if</span>( theta & 0x8000 ) y = -y;</div>
<div class="line"><a name="l00108"></a><span class="lineno"> 108</span> </div>
<div class="line"><a name="l00109"></a><span class="lineno"> 109</span>  <span class="keywordflow">return</span> y;</div>
<div class="line"><a name="l00110"></a><span class="lineno"> 110</span> }</div>
<div class="line"><a name="l00111"></a><span class="lineno"> 111</span> </div>
<div class="line"><a name="l00112"></a><span class="lineno"> 112</span> </div>
<div class="line"><a name="l00120"></a><span class="lineno"><a class="line" href="group___trig.html#ga056952ebed39f55880bb353857b47075"> 120</a></span> LIB8STATIC int16_t <a class="code" href="group___trig.html#ga056952ebed39f55880bb353857b47075">cos16</a>( uint16_t theta)</div>
<div class="line"><a name="l00121"></a><span class="lineno"> 121</span> {</div>
<div class="line"><a name="l00122"></a><span class="lineno"> 122</span>  <span class="keywordflow">return</span> sin16( theta + 16384);</div>
<div class="line"><a name="l00123"></a><span class="lineno"> 123</span> }</div>
<div class="line"><a name="l00124"></a><span class="lineno"> 124</span> </div>
<div class="line"><a name="l00126"></a><span class="lineno"> 126</span> </div>
<div class="line"><a name="l00127"></a><span class="lineno"> 127</span> <span class="comment">// sin8 & cos8</span></div>
<div class="line"><a name="l00128"></a><span class="lineno"> 128</span> <span class="comment">// Fast 8-bit approximations of sin(x) & cos(x).</span></div>
<div class="line"><a name="l00129"></a><span class="lineno"> 129</span> <span class="comment">// Input angle is an unsigned int from 0-255.</span></div>
<div class="line"><a name="l00130"></a><span class="lineno"> 130</span> <span class="comment">// Output is an unsigned int from 0 to 255.</span></div>
<div class="line"><a name="l00131"></a><span class="lineno"> 131</span> <span class="comment">//</span></div>
<div class="line"><a name="l00132"></a><span class="lineno"> 132</span> <span class="comment">// This approximation can vary to to 2%</span></div>
<div class="line"><a name="l00133"></a><span class="lineno"> 133</span> <span class="comment">// from the floating point value you'd get by doing</span></div>
<div class="line"><a name="l00134"></a><span class="lineno"> 134</span> <span class="comment">// float s = (sin( x ) * 128.0) + 128;</span></div>
<div class="line"><a name="l00135"></a><span class="lineno"> 135</span> <span class="comment">//</span></div>
<div class="line"><a name="l00136"></a><span class="lineno"> 136</span> <span class="comment">// Don't use this approximation for calculating the</span></div>
<div class="line"><a name="l00137"></a><span class="lineno"> 137</span> <span class="comment">// "real" trigonometric calculations, but it's great</span></div>
<div class="line"><a name="l00138"></a><span class="lineno"> 138</span> <span class="comment">// for art projects and LED displays.</span></div>
<div class="line"><a name="l00139"></a><span class="lineno"> 139</span> <span class="comment">//</span></div>
<div class="line"><a name="l00140"></a><span class="lineno"> 140</span> <span class="comment">// On Arduino/AVR, this approximation is more than</span></div>
<div class="line"><a name="l00141"></a><span class="lineno"> 141</span> <span class="comment">// 20X faster than floating point sin(x) and cos(x)</span></div>
<div class="line"><a name="l00142"></a><span class="lineno"> 142</span> </div>
<div class="line"><a name="l00143"></a><span class="lineno"> 143</span> <span class="preprocessor">#if defined(__AVR__) && !defined(LIB8_ATTINY)</span></div>
<div class="line"><a name="l00144"></a><span class="lineno"> 144</span> <span class="preprocessor">#define sin8 sin8_avr</span></div>
<div class="line"><a name="l00145"></a><span class="lineno"> 145</span> <span class="preprocessor">#else</span></div>
<div class="line"><a name="l00146"></a><span class="lineno"> 146</span> <span class="preprocessor">#define sin8 sin8_C</span></div>
<div class="line"><a name="l00147"></a><span class="lineno"> 147</span> <span class="preprocessor">#endif</span></div>
<div class="line"><a name="l00148"></a><span class="lineno"> 148</span> </div>
<div class="line"><a name="l00149"></a><span class="lineno"> 149</span> </div>
<div class="line"><a name="l00150"></a><span class="lineno"> 150</span> <span class="keyword">const</span> uint8_t b_m16_interleave[] = { 0, 49, 49, 41, 90, 27, 117, 10 };</div>
<div class="line"><a name="l00151"></a><span class="lineno"> 151</span> </div>
<div class="line"><a name="l00159"></a><span class="lineno"><a class="line" href="group___trig.html#ga6aa1f993cbbc427d80da1ee2ccca86e7"> 159</a></span> LIB8STATIC uint8_t <a class="code" href="group___trig.html#ga6aa1f993cbbc427d80da1ee2ccca86e7">sin8_avr</a>( uint8_t theta)</div>
<div class="line"><a name="l00160"></a><span class="lineno"> 160</span> {</div>
<div class="line"><a name="l00161"></a><span class="lineno"> 161</span>  uint8_t offset = theta;</div>
<div class="line"><a name="l00162"></a><span class="lineno"> 162</span> </div>
<div class="line"><a name="l00163"></a><span class="lineno"> 163</span>  <span class="keyword">asm</span> <span class="keyword">volatile</span>(</div>
<div class="line"><a name="l00164"></a><span class="lineno"> 164</span>  <span class="stringliteral">"sbrc %[theta],6 \n\t"</span></div>
<div class="line"><a name="l00165"></a><span class="lineno"> 165</span>  <span class="stringliteral">"com %[offset] \n\t"</span></div>
<div class="line"><a name="l00166"></a><span class="lineno"> 166</span>  : [theta] <span class="stringliteral">"+r"</span> (theta), [offset] <span class="stringliteral">"+r"</span> (offset)</div>
<div class="line"><a name="l00167"></a><span class="lineno"> 167</span>  );</div>
<div class="line"><a name="l00168"></a><span class="lineno"> 168</span> </div>
<div class="line"><a name="l00169"></a><span class="lineno"> 169</span>  offset &= 0x3F; <span class="comment">// 0..63</span></div>
<div class="line"><a name="l00170"></a><span class="lineno"> 170</span> </div>
<div class="line"><a name="l00171"></a><span class="lineno"> 171</span>  uint8_t secoffset = offset & 0x0F; <span class="comment">// 0..15</span></div>
<div class="line"><a name="l00172"></a><span class="lineno"> 172</span>  <span class="keywordflow">if</span>( theta & 0x40) secoffset++;</div>
<div class="line"><a name="l00173"></a><span class="lineno"> 173</span> </div>
<div class="line"><a name="l00174"></a><span class="lineno"> 174</span>  uint8_t m16; uint8_t b;</div>
<div class="line"><a name="l00175"></a><span class="lineno"> 175</span> </div>
<div class="line"><a name="l00176"></a><span class="lineno"> 176</span>  uint8_t section = offset >> 4; <span class="comment">// 0..3</span></div>
<div class="line"><a name="l00177"></a><span class="lineno"> 177</span>  uint8_t s2 = section * 2;</div>
<div class="line"><a name="l00178"></a><span class="lineno"> 178</span> </div>
<div class="line"><a name="l00179"></a><span class="lineno"> 179</span>  <span class="keyword">const</span> uint8_t* p = b_m16_interleave;</div>
<div class="line"><a name="l00180"></a><span class="lineno"> 180</span>  p += s2;</div>
<div class="line"><a name="l00181"></a><span class="lineno"> 181</span>  b = *p;</div>
<div class="line"><a name="l00182"></a><span class="lineno"> 182</span>  p++;</div>
<div class="line"><a name="l00183"></a><span class="lineno"> 183</span>  m16 = *p;</div>
<div class="line"><a name="l00184"></a><span class="lineno"> 184</span> </div>
<div class="line"><a name="l00185"></a><span class="lineno"> 185</span>  uint8_t mx;</div>
<div class="line"><a name="l00186"></a><span class="lineno"> 186</span>  uint8_t xr1;</div>
<div class="line"><a name="l00187"></a><span class="lineno"> 187</span>  <span class="keyword">asm</span> <span class="keyword">volatile</span>(</div>
<div class="line"><a name="l00188"></a><span class="lineno"> 188</span>  <span class="stringliteral">"mul %[m16],%[secoffset] \n\t"</span></div>
<div class="line"><a name="l00189"></a><span class="lineno"> 189</span>  <span class="stringliteral">"mov %[mx],r0 \n\t"</span></div>
<div class="line"><a name="l00190"></a><span class="lineno"> 190</span>  <span class="stringliteral">"mov %[xr1],r1 \n\t"</span></div>
<div class="line"><a name="l00191"></a><span class="lineno"> 191</span>  <span class="stringliteral">"eor r1, r1 \n\t"</span></div>
<div class="line"><a name="l00192"></a><span class="lineno"> 192</span>  <span class="stringliteral">"swap %[mx] \n\t"</span></div>
<div class="line"><a name="l00193"></a><span class="lineno"> 193</span>  <span class="stringliteral">"andi %[mx],0x0F \n\t"</span></div>
<div class="line"><a name="l00194"></a><span class="lineno"> 194</span>  <span class="stringliteral">"swap %[xr1] \n\t"</span></div>
<div class="line"><a name="l00195"></a><span class="lineno"> 195</span>  <span class="stringliteral">"andi %[xr1], 0xF0 \n\t"</span></div>
<div class="line"><a name="l00196"></a><span class="lineno"> 196</span>  <span class="stringliteral">"or %[mx], %[xr1] \n\t"</span></div>
<div class="line"><a name="l00197"></a><span class="lineno"> 197</span>  : [mx] <span class="stringliteral">"=r"</span> (mx), [xr1] <span class="stringliteral">"=r"</span> (xr1)</div>
<div class="line"><a name="l00198"></a><span class="lineno"> 198</span>  : [m16] <span class="stringliteral">"r"</span> (m16), [secoffset] <span class="stringliteral">"r"</span> (secoffset)</div>
<div class="line"><a name="l00199"></a><span class="lineno"> 199</span>  );</div>
<div class="line"><a name="l00200"></a><span class="lineno"> 200</span> </div>
<div class="line"><a name="l00201"></a><span class="lineno"> 201</span>  int8_t y = mx + b;</div>
<div class="line"><a name="l00202"></a><span class="lineno"> 202</span>  <span class="keywordflow">if</span>( theta & 0x80 ) y = -y;</div>
<div class="line"><a name="l00203"></a><span class="lineno"> 203</span> </div>
<div class="line"><a name="l00204"></a><span class="lineno"> 204</span>  y += 128;</div>
<div class="line"><a name="l00205"></a><span class="lineno"> 205</span> </div>
<div class="line"><a name="l00206"></a><span class="lineno"> 206</span>  <span class="keywordflow">return</span> y;</div>
<div class="line"><a name="l00207"></a><span class="lineno"> 207</span> }</div>
<div class="line"><a name="l00208"></a><span class="lineno"> 208</span> </div>
<div class="line"><a name="l00209"></a><span class="lineno"> 209</span> </div>
<div class="line"><a name="l00217"></a><span class="lineno"><a class="line" href="group___trig.html#ga46933a9b42921c6605588268d11f7c1e"> 217</a></span> LIB8STATIC uint8_t <a class="code" href="group___trig.html#ga46933a9b42921c6605588268d11f7c1e">sin8_C</a>( uint8_t theta)</div>
<div class="line"><a name="l00218"></a><span class="lineno"> 218</span> {</div>
<div class="line"><a name="l00219"></a><span class="lineno"> 219</span>  uint8_t offset = theta;</div>
<div class="line"><a name="l00220"></a><span class="lineno"> 220</span>  <span class="keywordflow">if</span>( theta & 0x40 ) {</div>
<div class="line"><a name="l00221"></a><span class="lineno"> 221</span>  offset = (uint8_t)255 - offset;</div>
<div class="line"><a name="l00222"></a><span class="lineno"> 222</span>  }</div>
<div class="line"><a name="l00223"></a><span class="lineno"> 223</span>  offset &= 0x3F; <span class="comment">// 0..63</span></div>
<div class="line"><a name="l00224"></a><span class="lineno"> 224</span> </div>
<div class="line"><a name="l00225"></a><span class="lineno"> 225</span>  uint8_t secoffset = offset & 0x0F; <span class="comment">// 0..15</span></div>
<div class="line"><a name="l00226"></a><span class="lineno"> 226</span>  <span class="keywordflow">if</span>( theta & 0x40) secoffset++;</div>
<div class="line"><a name="l00227"></a><span class="lineno"> 227</span> </div>
<div class="line"><a name="l00228"></a><span class="lineno"> 228</span>  uint8_t section = offset >> 4; <span class="comment">// 0..3</span></div>
<div class="line"><a name="l00229"></a><span class="lineno"> 229</span>  uint8_t s2 = section * 2;</div>
<div class="line"><a name="l00230"></a><span class="lineno"> 230</span>  <span class="keyword">const</span> uint8_t* p = b_m16_interleave;</div>
<div class="line"><a name="l00231"></a><span class="lineno"> 231</span>  p += s2;</div>
<div class="line"><a name="l00232"></a><span class="lineno"> 232</span>  uint8_t b = *p;</div>
<div class="line"><a name="l00233"></a><span class="lineno"> 233</span>  p++;</div>
<div class="line"><a name="l00234"></a><span class="lineno"> 234</span>  uint8_t m16 = *p;</div>
<div class="line"><a name="l00235"></a><span class="lineno"> 235</span> </div>
<div class="line"><a name="l00236"></a><span class="lineno"> 236</span>  uint8_t mx = (m16 * secoffset) >> 4;</div>
<div class="line"><a name="l00237"></a><span class="lineno"> 237</span> </div>
<div class="line"><a name="l00238"></a><span class="lineno"> 238</span>  int8_t y = mx + b;</div>
<div class="line"><a name="l00239"></a><span class="lineno"> 239</span>  <span class="keywordflow">if</span>( theta & 0x80 ) y = -y;</div>
<div class="line"><a name="l00240"></a><span class="lineno"> 240</span> </div>
<div class="line"><a name="l00241"></a><span class="lineno"> 241</span>  y += 128;</div>
<div class="line"><a name="l00242"></a><span class="lineno"> 242</span> </div>
<div class="line"><a name="l00243"></a><span class="lineno"> 243</span>  <span class="keywordflow">return</span> y;</div>
<div class="line"><a name="l00244"></a><span class="lineno"> 244</span> }</div>
<div class="line"><a name="l00245"></a><span class="lineno"> 245</span> </div>
<div class="line"><a name="l00253"></a><span class="lineno"><a class="line" href="group___trig.html#ga4432f985c94f5bff715db402d767b0e8"> 253</a></span> LIB8STATIC uint8_t <a class="code" href="group___trig.html#ga4432f985c94f5bff715db402d767b0e8">cos8</a>( uint8_t theta)</div>
<div class="line"><a name="l00254"></a><span class="lineno"> 254</span> {</div>
<div class="line"><a name="l00255"></a><span class="lineno"> 255</span>  <span class="keywordflow">return</span> sin8( theta + 64);</div>
<div class="line"><a name="l00256"></a><span class="lineno"> 256</span> }</div>
<div class="line"><a name="l00257"></a><span class="lineno"> 257</span> </div>
<div class="line"><a name="l00259"></a><span class="lineno"> 259</span> <span class="preprocessor">#endif</span></div>
<div class="ttc" id="group___trig_html_ga056952ebed39f55880bb353857b47075"><div class="ttname"><a href="group___trig.html#ga056952ebed39f55880bb353857b47075">cos16</a></div><div class="ttdeci">LIB8STATIC int16_t cos16(uint16_t theta)</div><div class="ttdoc">Fast 16-bit approximation of cos(x). </div><div class="ttdef"><b>Definition:</b> <a href="trig8_8h_source.html#l00120">trig8.h:120</a></div></div>
<div class="ttc" id="group___trig_html_ga4432f985c94f5bff715db402d767b0e8"><div class="ttname"><a href="group___trig.html#ga4432f985c94f5bff715db402d767b0e8">cos8</a></div><div class="ttdeci">LIB8STATIC uint8_t cos8(uint8_t theta)</div><div class="ttdoc">Fast 8-bit approximation of cos(x). </div><div class="ttdef"><b>Definition:</b> <a href="trig8_8h_source.html#l00253">trig8.h:253</a></div></div>
<div class="ttc" id="group___trig_html_ga6aa1f993cbbc427d80da1ee2ccca86e7"><div class="ttname"><a href="group___trig.html#ga6aa1f993cbbc427d80da1ee2ccca86e7">sin8_avr</a></div><div class="ttdeci">LIB8STATIC uint8_t sin8_avr(uint8_t theta)</div><div class="ttdoc">Fast 8-bit approximation of sin(x). </div><div class="ttdef"><b>Definition:</b> <a href="trig8_8h_source.html#l00159">trig8.h:159</a></div></div>
<div class="ttc" id="group___trig_html_ga0890962cb06b267617f4b06d7e9be5eb"><div class="ttname"><a href="group___trig.html#ga0890962cb06b267617f4b06d7e9be5eb">sin16_C</a></div><div class="ttdeci">LIB8STATIC int16_t sin16_C(uint16_t theta)</div><div class="ttdoc">Fast 16-bit approximation of sin(x). </div><div class="ttdef"><b>Definition:</b> <a href="trig8_8h_source.html#l00088">trig8.h:88</a></div></div>
<div class="ttc" id="group___trig_html_ga660ff60bfc5116525e50187de72009fc"><div class="ttname"><a href="group___trig.html#ga660ff60bfc5116525e50187de72009fc">sin16_avr</a></div><div class="ttdeci">LIB8STATIC int16_t sin16_avr(uint16_t theta)</div><div class="ttdoc">Fast 16-bit approximation of sin(x). </div><div class="ttdef"><b>Definition:</b> <a href="trig8_8h_source.html#l00030">trig8.h:30</a></div></div>
<div class="ttc" id="group___trig_html_ga46933a9b42921c6605588268d11f7c1e"><div class="ttname"><a href="group___trig.html#ga46933a9b42921c6605588268d11f7c1e">sin8_C</a></div><div class="ttdeci">LIB8STATIC uint8_t sin8_C(uint8_t theta)</div><div class="ttdoc">Fast 8-bit approximation of sin(x). </div><div class="ttdef"><b>Definition:</b> <a href="trig8_8h_source.html#l00217">trig8.h:217</a></div></div>
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