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| <h1>include/core/SkMath.h File Reference</h1><code>#include "<a class="el" href="_sk_types_8h_source.html">SkTypes.h</a>"</code><br/> |
| <div class="dynheader"> |
| Include dependency graph for SkMath.h:</div> |
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| This graph shows which files directly or indirectly include this file:</div> |
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| <p><a href="_sk_math_8h_source.html">Go to the source code of this file.</a></p> |
| <table border="0" cellpadding="0" cellspacing="0"> |
| <tr><td colspan="2"><h2>Defines</h2></td></tr> |
| <tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="_sk_math_8h.html#afab08772cf54af5b56983cba9fa509c3">SkSqrt32</a>(n) SkSqrtBits(n, 15)</td></tr> |
| <tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="_sk_math_8h.html#abf04f1dc3004c0ed8b5fa535e81da59d">SkExtractSign</a>(n) ((int32_t)(n) >> 31)</td></tr> |
| <tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="_sk_math_8h.html#a238d25f0a1156c6f2c652e9b7ab78277">SkCLZ</a>(x) SkCLZ_portable(x)</td></tr> |
| <tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="_sk_math_8h.html#ac995b5abe886001a2be1b63bb652f0c9">SkMulS16</a>(x, y) ((x) * (y))</td></tr> |
| <tr><td colspan="2"><h2>Functions</h2></td></tr> |
| <tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="_sk_math_8h.html#a84fb2d86b39452eef0b8a614b8bd7578">SkCLZ_portable</a> (uint32_t)</td></tr> |
| <tr><td class="mdescLeft"> </td><td class="mdescRight">Returns the number of leading zero bits (0...32). <a href="#a84fb2d86b39452eef0b8a614b8bd7578"></a><br/></td></tr> |
| <tr><td class="memItemLeft" align="right" valign="top">int32_t </td><td class="memItemRight" valign="bottom"><a class="el" href="_sk_math_8h.html#ad1c82f373d385a5821da3a186d93c5ce">SkMulShift</a> (int32_t a, int32_t b, unsigned shift)</td></tr> |
| <tr><td class="memItemLeft" align="right" valign="top">int32_t </td><td class="memItemRight" valign="bottom"><a class="el" href="_sk_math_8h.html#ae43bef67fd5c320215fe2cfdb6ab35ca">SkMulDiv</a> (int32_t numer1, int32_t numer2, int32_t denom)</td></tr> |
| <tr><td class="memItemLeft" align="right" valign="top">int32_t </td><td class="memItemRight" valign="bottom"><a class="el" href="_sk_math_8h.html#a1d093e44b78bf74cdbbc42cc60fad438">SkDivBits</a> (int32_t numer, int32_t denom, int shift)</td></tr> |
| <tr><td class="memItemLeft" align="right" valign="top">int32_t </td><td class="memItemRight" valign="bottom"><a class="el" href="_sk_math_8h.html#ab6325ae5ffed98c2af87ef1b37a3411d">SkSqrtBits</a> (int32_t value, int bitBias)</td></tr> |
| <tr><td class="memItemLeft" align="right" valign="top">int32_t </td><td class="memItemRight" valign="bottom"><a class="el" href="_sk_math_8h.html#afae7d95657f0e3f7ed82e814548ad481">SkCubeRootBits</a> (int32_t value, int bitBias)</td></tr> |
| </table> |
| <hr/><h2>Define Documentation</h2> |
| <a class="anchor" id="a238d25f0a1156c6f2c652e9b7ab78277"></a><!-- doxytag: member="SkMath.h::SkCLZ" ref="a238d25f0a1156c6f2c652e9b7ab78277" args="(x)" --> |
| <div class="memitem"> |
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| <table class="memname"> |
| <tr> |
| <td class="memname">#define SkCLZ</td> |
| <td>(</td> |
| <td class="paramtype">x </td> |
| <td class="paramname"></td> |
| <td> ) </td> |
| <td> SkCLZ_portable(x)</td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| |
| <p>Definition at line <a class="el" href="_sk_math_8h_source.html#l00132">132</a> of file <a class="el" href="_sk_math_8h_source.html">SkMath.h</a>.</p> |
| |
| </div> |
| </div> |
| <a class="anchor" id="abf04f1dc3004c0ed8b5fa535e81da59d"></a><!-- doxytag: member="SkMath.h::SkExtractSign" ref="abf04f1dc3004c0ed8b5fa535e81da59d" args="(n)" --> |
| <div class="memitem"> |
| <div class="memproto"> |
| <table class="memname"> |
| <tr> |
| <td class="memname">#define SkExtractSign</td> |
| <td>(</td> |
| <td class="paramtype">n </td> |
| <td class="paramname"></td> |
| <td> ) </td> |
| <td> ((int32_t)(n) >> 31)</td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| <p>Returns -1 if n < 0, else returns 0 </p> |
| |
| <p>Definition at line <a class="el" href="_sk_math_8h_source.html#l00057">57</a> of file <a class="el" href="_sk_math_8h_source.html">SkMath.h</a>.</p> |
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| </div> |
| </div> |
| <a class="anchor" id="ac995b5abe886001a2be1b63bb652f0c9"></a><!-- doxytag: member="SkMath.h::SkMulS16" ref="ac995b5abe886001a2be1b63bb652f0c9" args="(x, y)" --> |
| <div class="memitem"> |
| <div class="memproto"> |
| <table class="memname"> |
| <tr> |
| <td class="memname">#define SkMulS16</td> |
| <td>(</td> |
| <td class="paramtype">x, </td> |
| </tr> |
| <tr> |
| <td class="paramkey"></td> |
| <td></td> |
| <td class="paramtype">y </td> |
| <td class="paramname"></td> |
| <td> ) </td> |
| <td> ((x) * (y))</td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| <p><a class="el" href="_sk_math_8h.html#ac995b5abe886001a2be1b63bb652f0c9">SkMulS16(a, b)</a> multiplies a * b, but requires that a and b are both int16_t. With this requirement, we can generate faster instructions on some architectures. </p> |
| |
| <p>Definition at line <a class="el" href="_sk_math_8h_source.html#l00187">187</a> of file <a class="el" href="_sk_math_8h_source.html">SkMath.h</a>.</p> |
| |
| </div> |
| </div> |
| <a class="anchor" id="afab08772cf54af5b56983cba9fa509c3"></a><!-- doxytag: member="SkMath.h::SkSqrt32" ref="afab08772cf54af5b56983cba9fa509c3" args="(n)" --> |
| <div class="memitem"> |
| <div class="memproto"> |
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| <td class="memname">#define SkSqrt32</td> |
| <td>(</td> |
| <td class="paramtype">n </td> |
| <td class="paramname"></td> |
| <td> ) </td> |
| <td> SkSqrtBits(n, 15)</td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| <p>Return the integer square root of n, treated as a SkFixed (16.16) </p> |
| |
| <p>Definition at line <a class="el" href="_sk_math_8h_source.html#l00049">49</a> of file <a class="el" href="_sk_math_8h_source.html">SkMath.h</a>.</p> |
| |
| </div> |
| </div> |
| <hr/><h2>Function Documentation</h2> |
| <a class="anchor" id="a84fb2d86b39452eef0b8a614b8bd7578"></a><!-- doxytag: member="SkMath.h::SkCLZ_portable" ref="a84fb2d86b39452eef0b8a614b8bd7578" args="(uint32_t)" --> |
| <div class="memitem"> |
| <div class="memproto"> |
| <table class="memname"> |
| <tr> |
| <td class="memname">int SkCLZ_portable </td> |
| <td>(</td> |
| <td class="paramtype">uint32_t </td> |
| <td class="paramname"></td> |
| <td> ) </td> |
| <td></td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| |
| <p>Returns the number of leading zero bits (0...32). </p> |
| |
| </div> |
| </div> |
| <a class="anchor" id="afae7d95657f0e3f7ed82e814548ad481"></a><!-- doxytag: member="SkMath.h::SkCubeRootBits" ref="afae7d95657f0e3f7ed82e814548ad481" args="(int32_t value, int bitBias)" --> |
| <div class="memitem"> |
| <div class="memproto"> |
| <table class="memname"> |
| <tr> |
| <td class="memname">int32_t SkCubeRootBits </td> |
| <td>(</td> |
| <td class="paramtype">int32_t </td> |
| <td class="paramname"> <em>value</em>, </td> |
| </tr> |
| <tr> |
| <td class="paramkey"></td> |
| <td></td> |
| <td class="paramtype">int </td> |
| <td class="paramname"> <em>bitBias</em></td><td> </td> |
| </tr> |
| <tr> |
| <td></td> |
| <td>)</td> |
| <td></td><td></td><td></td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| <p>Return the integer cube root of value, with a bias of bitBias </p> |
| |
| </div> |
| </div> |
| <a class="anchor" id="a1d093e44b78bf74cdbbc42cc60fad438"></a><!-- doxytag: member="SkMath.h::SkDivBits" ref="a1d093e44b78bf74cdbbc42cc60fad438" args="(int32_t numer, int32_t denom, int shift)" --> |
| <div class="memitem"> |
| <div class="memproto"> |
| <table class="memname"> |
| <tr> |
| <td class="memname">int32_t SkDivBits </td> |
| <td>(</td> |
| <td class="paramtype">int32_t </td> |
| <td class="paramname"> <em>numer</em>, </td> |
| </tr> |
| <tr> |
| <td class="paramkey"></td> |
| <td></td> |
| <td class="paramtype">int32_t </td> |
| <td class="paramname"> <em>denom</em>, </td> |
| </tr> |
| <tr> |
| <td class="paramkey"></td> |
| <td></td> |
| <td class="paramtype">int </td> |
| <td class="paramname"> <em>shift</em></td><td> </td> |
| </tr> |
| <tr> |
| <td></td> |
| <td>)</td> |
| <td></td><td></td><td></td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| <p>Computes (numer1 << shift) / denom in full 64 intermediate precision. It is an error for denom to be 0. There is no special handling if the result overflows 32bits. </p> |
| |
| </div> |
| </div> |
| <a class="anchor" id="ae43bef67fd5c320215fe2cfdb6ab35ca"></a><!-- doxytag: member="SkMath.h::SkMulDiv" ref="ae43bef67fd5c320215fe2cfdb6ab35ca" args="(int32_t numer1, int32_t numer2, int32_t denom)" --> |
| <div class="memitem"> |
| <div class="memproto"> |
| <table class="memname"> |
| <tr> |
| <td class="memname">int32_t SkMulDiv </td> |
| <td>(</td> |
| <td class="paramtype">int32_t </td> |
| <td class="paramname"> <em>numer1</em>, </td> |
| </tr> |
| <tr> |
| <td class="paramkey"></td> |
| <td></td> |
| <td class="paramtype">int32_t </td> |
| <td class="paramname"> <em>numer2</em>, </td> |
| </tr> |
| <tr> |
| <td class="paramkey"></td> |
| <td></td> |
| <td class="paramtype">int32_t </td> |
| <td class="paramname"> <em>denom</em></td><td> </td> |
| </tr> |
| <tr> |
| <td></td> |
| <td>)</td> |
| <td></td><td></td><td></td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| <p>Computes numer1 * numer2 / denom in full 64 intermediate precision. It is an error for denom to be 0. There is no special handling if the result overflows 32bits. </p> |
| |
| </div> |
| </div> |
| <a class="anchor" id="ad1c82f373d385a5821da3a186d93c5ce"></a><!-- doxytag: member="SkMath.h::SkMulShift" ref="ad1c82f373d385a5821da3a186d93c5ce" args="(int32_t a, int32_t b, unsigned shift)" --> |
| <div class="memitem"> |
| <div class="memproto"> |
| <table class="memname"> |
| <tr> |
| <td class="memname">int32_t SkMulShift </td> |
| <td>(</td> |
| <td class="paramtype">int32_t </td> |
| <td class="paramname"> <em>a</em>, </td> |
| </tr> |
| <tr> |
| <td class="paramkey"></td> |
| <td></td> |
| <td class="paramtype">int32_t </td> |
| <td class="paramname"> <em>b</em>, </td> |
| </tr> |
| <tr> |
| <td class="paramkey"></td> |
| <td></td> |
| <td class="paramtype">unsigned </td> |
| <td class="paramname"> <em>shift</em></td><td> </td> |
| </tr> |
| <tr> |
| <td></td> |
| <td>)</td> |
| <td></td><td></td><td></td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| <p>Computes the 64bit product of a * b, and then shifts the answer down by shift bits, returning the low 32bits. shift must be [0..63] e.g. to perform a fixedmul, call SkMulShift(a, b, 16) </p> |
| |
| </div> |
| </div> |
| <a class="anchor" id="ab6325ae5ffed98c2af87ef1b37a3411d"></a><!-- doxytag: member="SkMath.h::SkSqrtBits" ref="ab6325ae5ffed98c2af87ef1b37a3411d" args="(int32_t value, int bitBias)" --> |
| <div class="memitem"> |
| <div class="memproto"> |
| <table class="memname"> |
| <tr> |
| <td class="memname">int32_t SkSqrtBits </td> |
| <td>(</td> |
| <td class="paramtype">int32_t </td> |
| <td class="paramname"> <em>value</em>, </td> |
| </tr> |
| <tr> |
| <td class="paramkey"></td> |
| <td></td> |
| <td class="paramtype">int </td> |
| <td class="paramname"> <em>bitBias</em></td><td> </td> |
| </tr> |
| <tr> |
| <td></td> |
| <td>)</td> |
| <td></td><td></td><td></td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| <p>Return the integer square root of value, with a bias of bitBias </p> |
| |
| </div> |
| </div> |
| </div> |
| <hr size="1"/><address style="text-align: right;"><small>Generated on Tue Oct 20 11:03:40 2009 for Skia by |
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