游戏是这样写成的（第四篇：缩放和混色）

Admin

<div class="ostContent"><span style="COLOR: rgb(51,51,51)"><span class="Apple-style-span" style="FONT-STYLE: italic">
<p><img height="742" alt="" src="http://www.cocoachina.com/bbs/attachment/6_37_908f121fd07cf08.jpg" width="386"/></p>
<p>在群里有同学们为了怎样用OpenGL ES缩放图像而烦恼，正好我也很久没更新这个教程了，所以把第三篇的代码更新了一下，加了缩放和混色功能。</p>
<p><span id="more-266"></span></p>
<p>我也用了SDK Final的模块，重新建立了一次项目。</p>
<p>这次的修改，主要是CCSprite的render，大家可以参考一下，怎么用glScalef来做缩放。</p>
<div class="geshi no=" objc? no?>
<ol>
<li class="li1">
<div class="de1"><span class="kw4">void</span> CCSprite<span class="sy0">::</span><span class="kw4">render</span><span class="br0">(</span><span class="kw4">float</span> x, <span class="kw4">float</span> <span class="kw4">y</span>, <span class="kw4">float</span> angle, <span class="kw4">float</span> xScale, <span class="kw4">float</span> yScale<span class="br0">)</span></div>
<li class="li1">
<div class="de1"><span class="br0">{</span></div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; <span class="kw4">y</span> <span class="sy0">=</span> SCREEN_HEIGHT<span class="sy0">-</span><span class="kw4">y</span>; &nbsp; &nbsp; &nbsp; &nbsp;<span class="co1">// for OpenGL ES, (0,0) is at lower left corner!</span></div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; </div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; GLfloat _minU <span class="sy0">=</span> mX<span class="sy0">/</span>mTexture<span class="sy0">-</span>&gt;getTextureWidth<span class="br0">(</span><span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; GLfloat _maxU <span class="sy0">=</span> <span class="br0">(</span>mX<span class="sy0">+</span>mWidth<span class="br0">)</span><span class="sy0">/</span>mTexture<span class="sy0">-</span>&gt;getTextureWidth<span class="br0">(</span><span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; GLfloat _minV <span class="sy0">=</span> mY<span class="sy0">/</span>mTexture<span class="sy0">-</span>&gt;getTextureHeight<span class="br0">(</span><span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; GLfloat _maxV <span class="sy0">=</span> <span class="br0">(</span>mY<span class="sy0">+</span>mHeight<span class="br0">)</span><span class="sy0">/</span>mTexture<span class="sy0">-</span>&gt;getTextureHeight<span class="br0">(</span><span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; </div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; GLfloat &nbsp; &nbsp;coordinates<span class="br0">[</span><span class="br0">]</span> <span class="sy0">=</span> </div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; <span class="br0">{</span></div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; &nbsp; &nbsp; _minU, &nbsp; &nbsp;_maxV,</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; &nbsp; &nbsp; _maxU, &nbsp; &nbsp;_maxV,</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; &nbsp; &nbsp; _minU, &nbsp; &nbsp;_minV,</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; &nbsp; &nbsp; _maxU, &nbsp; &nbsp;_minV</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; <span class="br0">}</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; </div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; GLfloat &nbsp; &nbsp;xx <span class="sy0">=</span> <span class="sy0">-</span> mWidth<span class="sy0">/</span><span class="nu0">2</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; GLfloat yy <span class="sy0">=</span> <span class="sy0">-</span> mHeight<span class="sy0">/</span><span class="nu0">2</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; </div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; GLfloat &nbsp; &nbsp;vertices<span class="br0">[</span><span class="br0">]</span> <span class="sy0">=</span> </div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; <span class="br0">{</span></div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; &nbsp; &nbsp; xx, &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;yy, &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; &nbsp; &nbsp; xx<span class="sy0">+</span>mWidth, &nbsp; &nbsp;yy, &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; &nbsp; &nbsp; xx, &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;yy<span class="sy0">+</span>mHeight,</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; &nbsp; &nbsp; xx<span class="sy0">+</span>mWidth, &nbsp; &nbsp;yy<span class="sy0">+</span>mHeight &nbsp; &nbsp;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; <span class="br0">}</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; </div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; mTexture<span class="sy0">-</span>&gt;bind<span class="br0">(</span><span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; </div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; glColor4f<span class="br0">(</span>mRed, mGreen, mBlue, mAlpha<span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; </div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; glPushMatrix<span class="br0">(</span><span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; glTranslatef<span class="br0">(</span>x, <span class="kw4">y</span>, <span class="nu0">0</span>.0f<span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; glRotatef<span class="br0">(</span>angle, <span class="nu0">0</span>.0f, <span class="nu0">0</span>.0f, <span class="nu0">1</span>.0f<span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; glScalef<span class="br0">(</span>xScale, yScale, <span class="nu0">1</span>.0f<span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; glVertexPointer<span class="br0">(</span><span class="nu0">2</span>, GL_FLOAT, <span class="nu0">0</span>, vertices<span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; glTexCoordPointer<span class="br0">(</span><span class="nu0">2</span>, GL_FLOAT, <span class="nu0">0</span>, coordinates<span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; glDrawArrays<span class="br0">(</span>GL_TRIANGLE_STRIP, <span class="nu0">0</span>, <span class="nu0">4</span><span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; glPopMatrix<span class="br0">(</span><span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; </div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; glColor4f<span class="br0">(</span><span class="nu0">1</span>.0f, <span class="nu0">1</span>.0f, <span class="nu0">1</span>.0f, <span class="nu0">1</span>.0f<span class="br0">)</span>;</div>
<li class="li1">
<div class="de1">&nbsp; &nbsp; </div>
<li class="li1">
<div class="de1"><span class="br0">}</span></div></li></ol></div>
<p>本文例子代码在<a href="http://www.cocoachina.com/bbs/read.php?tid-487-toread-1.html" target="_blank">这里</a>，请登录后下载。</p></span></span>
<p>&nbsp;</p></div>