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-rw-r--r--docs/html/guide/topics/graphics/hardware-accel.jd355
-rw-r--r--docs/html/guide/topics/graphics/renderscript/graphics.jd994
2 files changed, 251 insertions, 1098 deletions
diff --git a/docs/html/guide/topics/graphics/hardware-accel.jd b/docs/html/guide/topics/graphics/hardware-accel.jd
index 04fb564..9859c28 100644
--- a/docs/html/guide/topics/graphics/hardware-accel.jd
+++ b/docs/html/guide/topics/graphics/hardware-accel.jd
@@ -270,110 +270,257 @@ changed.</li>
android.graphics.Canvas} drawing operations as well as many less-used operations. All of the
drawing operations that are used to render applications that ship with Android, default widgets
and layouts, and common advanced visual effects such as reflections and tiled textures are
- supported. The following list describes known operations that are <strong>not supported</strong>
- with hardware acceleration:</p>
-
- <ul>
- <li>
- <strong>Canvas</strong>
-
- <ul>
- <li>{@link android.graphics.Canvas#clipPath clipPath()}</li>
-
- <li>{@link android.graphics.Canvas#clipRegion clipRegion()}</li>
-
- <li>{@link android.graphics.Canvas#drawPicture drawPicture()}</li>
-
- <li>{@link android.graphics.Canvas#drawTextOnPath drawTextOnPath()}</li>
-
- <li>{@link android.graphics.Canvas#drawVertices drawVertices()}</li>
- </ul>
- </li>
-
- <li>
- <strong>Paint</strong>
-
- <ul>
- <li>{@link android.graphics.Paint#setLinearText setLinearText()}</li>
-
- <li>{@link android.graphics.Paint#setMaskFilter setMaskFilter()}</li>
-
- <li>{@link android.graphics.Paint#setRasterizer setRasterizer()}</li>
- </ul>
- </li>
-
- <li>
- <strong>Xfermodes</strong>
-
- <ul>
- <li>{@link android.graphics.AvoidXfermode AvoidXfermode}</li>
-
- <li>{@link android.graphics.PixelXorXfermode PixelXorXfermode}</li>
- </ul>
- </li>
- </ul>
-
- <p>In addition, some operations behave differently with hardware acceleration enabled:</p>
-
- <ul>
- <li>
- <strong>Canvas</strong>
-
- <ul>
- <li>{@link android.graphics.Canvas#clipRect clipRect()}: <code>XOR</code>,
- <code>Difference</code> and <code>ReverseDifference</code> clip modes are ignored. 3D
- transforms do not apply to the clip rectangle</li>
-
- <li>{@link android.graphics.Canvas#drawBitmapMesh drawBitmapMesh()}: colors array is
- ignored</li>
- </ul>
- </li>
-
- <li>
- <strong>Paint</strong>
-
- <ul>
- <li>{@link android.graphics.Paint#setDither setDither()}: ignored</li>
-
- <li>{@link android.graphics.Paint#setFilterBitmap setFilterBitmap()}: filtering is always
- on</li>
-
- <li>{@link android.graphics.Paint#setShadowLayer setShadowLayer()}: works with text
- only</li>
- </ul>
- </li>
-
- <li>
- <strong>PorterDuffXfermode</strong>
-
- <ul>
- <li>{@link android.graphics.PorterDuff.Mode#DARKEN PorterDuff.Mode.DARKEN} will
- be equivalent to {@link android.graphics.PorterDuff.Mode#SRC_OVER} when blending
- against the framebuffer.</li>
-
- <li>{@link android.graphics.PorterDuff.Mode#LIGHTEN PorterDuff.Mode.LIGHTEN} will
- be equivalent to {@link android.graphics.PorterDuff.Mode#SRC_OVER} when blending
- against the framebuffer.</li>
-
- <li>{@link android.graphics.PorterDuff.Mode#OVERLAY PorterDuff.Mode.OVERLAY} will
- be equivalent to {@link android.graphics.PorterDuff.Mode#SRC_OVER} when blending
- against the framebuffer.</li>
- </ul>
- </li>
-
- <li>
- <strong>ComposeShader</strong>
-
- <ul>
- <li>{@link android.graphics.ComposeShader} can only contain shaders of different types (a
- {@link android.graphics.BitmapShader} and a {@link android.graphics.LinearGradient} for
- instance, but not two instances of {@link android.graphics.BitmapShader} )</li>
-
- <li>{@link android.graphics.ComposeShader} cannot contain a {@link
- android.graphics.ComposeShader}</li>
- </ul>
- </li>
- </ul>
+ supported.</p>
+
+ <p>The following table describes the support level of various operations across API levels:</p>
+
+ <style type="text/css">
+ .tblGenFixed,.tblGeneric{font-size:15px}.tblGenFixed td {padding:0 3px;letter-spacing:0;word-spacing:0;background-color:#fff;z-index:1;border-top:0px none;border-left:0px none;border-bottom:1px solid #CCC;border-right:1px solid #CCC;} .dn {display:none} .tblGenFixed td.s0 {background-color:white;border-top:1px solid #CCC;border-left:1px solid #CCC;} .tblGenFixed td.s2 {background-color:#d9d9d9;color:#000000;text-align:center;} .tblGenFixed td.s1 {background-color:#434343;color:#ffffff;text-align:center;border-top:1px solid #CCC;} .tblGenFixed td.s9 {background-color:;color:#6aa84f;text-align:center;} .tblGenFixed td.s12 {background-color:white;color:#6aa84f;text-align:center;} .tblGenFixed td.s13 {background-color:#d9d9d9;color:#6aa84f;text-align:center;} .tblGenFixed td.s7 {background-color:#d9d9d9;color:#980000;text-align:center;} .tblGenFixed td.s8 {background-color:;color:#980000;text-align:center;} .tblGenFixed td.s5 {background-color:#434343;color:#ffffff;text-align:left;border-left:1px solid #CCC;} .tblGenFixed td.s6 {background-color:;font-family:courier new,monospace;color:;text-align:right;border-left:1px solid #CCC;} .tblGenFixed td.s10 {background-color:white;font-family:courier new,monospace;color:#000000;text-align:right;border-left:1px solid #CCC;} .tblGenFixed td.s3 {background-color:white;color:#000000;text-align:center;} .tblGenFixed td.s11 {background-color:white;color:#980000;text-align:center;} .tblGenFixed td.s4 {background-color:#d9d9d9;color:#000000;text-align:center;}
+ </style>
+ <table border="0" cellpadding="0" cellspacing="0" class="tblGenFixed" id="tblMain">
+ <tbody>
+ <tr class="rShim">
+ <td class="rShim" style="width:380px;"></td>
+ <td class="rShim" style="width:120px;"></td>
+ <td class="rShim" style="width:120px;"></td>
+ <td class="rShim" style="width:120px;"></td>
+ <td class="rShim" style="width:120px;"></td>
+ </tr>
+ <tr>
+ <td rowspan="2" class="s0"></td>
+ <td colspan="4" class="s1">API level</td>
+ </tr>
+ <tr>
+ <td style="display:none;"></td>
+ <td class="s2">&lt; 16</td>
+ <td class="s3">16</td>
+ <td class="s4">17</td>
+ <td class="s3">18</td>
+ </tr>
+ <tr>
+ <td colspan="5" class="s5">Canvas</td>
+ </tr>
+ <tr>
+ <td class="s6">clipPath()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s8">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s9">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s10">clipRegion()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s10">clipRect(Region.Op.XOR)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s10">clipRect(Region.Op.Difference)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s10">clipRect(Region.Op.ReverseDifference)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s10">drawBitmapMesh() (colors array)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s10">drawPicture()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">drawPosText()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s12">&#10003;</td>
+ <td class="s13">&#10003;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s10">drawTextOnPath()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s12">&#10003;</td>
+ <td class="s13">&#10003;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s10">drawVertices()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">setDrawFilter()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s12">&#10003;</td>
+ <td class="s13">&#10003;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td colspan="5" class="s5">Paint</td>
+ </tr>
+ <tr>
+ <td class="s6">setAntiAlias() (for text)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s6">setAntiAlias() (for lines)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s12">&#10003;</td>
+ <td class="s13">&#10003;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s6">setFilterBitmap()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s13">&#10003;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s6">setLinearText()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s8">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s8">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">setMaskFilter()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">setPathEffect() (for lines)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">setRasterizer()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">setShadowLayer() (other than text)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">setStrokeCap() (for lines)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s12">&#10003;</td>
+ </tr>
+ <tr>
+ <td class="s10">setStrokeCap() (for points)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">setSubpixelText()</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td colspan="5" class="s5">Xfermode</td>
+ </tr>
+ <tr>
+ <td class="s6">AvoidXfermode</td>
+ <td class="s7">&#10007;</td>
+ <td class="s8">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s8">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">PixelXorXfermode</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">PorterDuff.Mode.DARKEN (framebuffer)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s8">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s8">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">PorterDuff.Mode.LIGHTEN (framebuffer)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">PorterDuff.Mode.OVERLAY (framebuffer)</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td colspan="5" class="s5">Shader</td>
+ </tr>
+ <tr>
+ <td class="s10">ComposeShader inside ComposeShader</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">Same type shaders inside ComposeShader</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ </tr>
+ <tr>
+ <td class="s10">Local matrix on ComposeShader</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10007;</td>
+ <td class="s7">&#10007;</td>
+ <td class="s11">&#10003;</td>
+ </tr>
+ </tbody>
+ </table>
<p>If your application is affected by any of these missing features or limitations, you can turn
off hardware acceleration for just the affected portion of your application by calling
diff --git a/docs/html/guide/topics/graphics/renderscript/graphics.jd b/docs/html/guide/topics/graphics/renderscript/graphics.jd
deleted file mode 100644
index 58676ea..0000000
--- a/docs/html/guide/topics/graphics/renderscript/graphics.jd
+++ /dev/null
@@ -1,994 +0,0 @@
-page.title=Graphics
-parent.title=Renderscript
-parent.link=index.html
-
-@jd:body
-
- <div id="qv-wrapper">
- <div id="qv">
- <h2>In this document</h2>
-
- <ol>
- <li>
- <a href="#creating-graphics-rs">Creating a Graphics Renderscript</a>
- <ol>
- <li><a href="#creating-native">Creating the Renderscript file</a></li>
- <li><a href="#creating-entry">Creating the Renderscript entry point class</a></li>
- <li><a href="#creating-view">Creating the view class</a></li>
- <li><a href="#creating-activity">Creating the activity class</a></li>
- </ol>
- </li>
- <li>
- <a href="#drawing">Drawing</a>
- <ol>
- <li><a href="#drawing-rsg">Simple drawing</a></li>
- <li><a href="#drawing-mesh">Drawing with a mesh</a></li>
- </ol>
- </li>
- <li>
- <a href="#shaders">Shaders</a>
- <ol>
- <li><a href="#shader-bindings">Shader bindings</a></li>
- <li><a href="#shader-sampler">Defining a sampler</a></li>
- </ol>
- </li>
- <li>
- <a href="#fbo">Rendering to a Framebuffer Object</a>
- </li>
- </ol>
-
- <h2>Related Samples</h2>
-
- <ol>
- <li><a href="{@docRoot}resources/samples/RenderScript/Balls/index.html">Balls</a></li>
-
- <li><a href="{@docRoot}resources/samples/RenderScript/Fountain/index.html">Fountain</a></li>
-
- <li><a href="{@docRoot}resources/samples/RenderScript/FountainFbo/index.html">FountainFbo</a></li>
-
- <li><a href="{@docRoot}resources/samples/RenderScript/HelloWorld/index.html">Hello
-World</a></li>
-
- <li><a
-href="{@docRoot}resources/samples/RenderScript/MiscSamples/index.html">Misc Samples</a></li>
- </ol>
- </div>
- </div>
-
- <p>Renderscript provides a number of graphics APIs for rendering, both at the Android
- framework level as well as at the Renderscript runtime level. For instance, the Android framework APIs let you
- create meshes and define shaders to customize the graphical rendering pipeline. The native
- Renderscript graphics APIs let you draw the actual meshes to render your scene. You need to
- be familiar with both APIs to appropriately render graphics on an Android-powered device.</p>
-
- <h2 id="creating-graphics-rs">Creating a Graphics Renderscript</h2>
-
- <p>Renderscript applications require various layers of code, so it is useful to create the following
- files to help keep your application organized:</p>
-
- <dl>
- <dt>The Renderscript <code>.rs</code> file</dt>
-
- <dd>This file contains the logic to do the graphics rendering.</dd>
-
- <dt>The Renderscript entry point <code>.java</code> class</dt>
-
- <dd>This class allows the view class to interact with the code defined in the <code>.rs</code>
- file. This class contains a Renderscript object (instance of
- <code>ScriptC_<em>renderscript_file</em></code>), which allows your Android framework code to
- call the Renderscript code. In general, this class does much of the setup for Renderscript
- such as shader and mesh building and memory allocation and binding. The SDK samples follow the
- convention of naming this file ActivityRS.java,
- where Activity is the name of your main activity class.</dd>
-
- <dt>The view <code>.java</code> class</dt>
-
- <dd>This class extends {@link android.renderscript.RSSurfaceView} or {@link
- android.renderscript.RSTextureView} to provide a surface to render on. A {@link
- android.renderscript.RSSurfaceView} consumes a whole window, but a {@link
- android.renderscript.RSTextureView} allows you to draw Renderscript graphics inside of a
- view and add it to a {@link android.view.ViewGroup} alongside
- other views. In this class, you create a {@link android.renderscript.RenderScriptGL} context object
- with a call to {@link android.renderscript.RSSurfaceView#createRenderScriptGL
- RSSurfaceView.createRenderscriptGL()} or {@link android.renderscript.RSTextureView#createRenderScriptGL
- RSTextureView.createRenderscriptGL()}. The {@link android.renderscript.RenderScriptGL} context object
- contains information about the current rendering state of Renderscript such as the vertex and
- fragment shaders. You pass this context object to the Renderscript entry point class, so that
- class can modify the rendering context if needed and bind the Renderscript code to the context. Once bound,
- the view class can use the Renderscript code to display graphics.
- The view class should also implement callbacks for events inherited from {@link
- android.view.View}, such as {@link android.view.View#onTouchEvent onTouchEvent()} and {@link
- android.view.View#onKeyDown onKeyDown()} if you want to detect these types of user interactions.
- The SDK samples follow the convention of naming this file ActivityView.java,
- where Activity is the name of your main activity class</dd>
-
- <dt>The activity <code>.java</code> class</dt>
-
- <dd>This class is the main activity class and sets your {@link android.renderscript.RSSurfaceView} as the main content
- view for this activity or uses the {@link android.renderscript.RSTextureView} alongside other views.</dd>
- </dl>
- <p>Figure 1 describes how these classes interact with one another in a graphics Renderscript:</p>
-
- <img src="{@docRoot}images/rs_graphics.png">
- <p class="img-caption"><strong>Figure 1.</strong> Graphics Renderscript overview</p>
-
-
- <p>The following sections describe how to create an application that uses a graphics Renderscript by using
- the <a href="{@docRoot}resources/samples/RenderScript/Fountain/index.html">Renderscript Fountain
- sample</a> that is provided in the SDK as a guide (some code has been modified from its original
- form for simplicity).</p>
-
- <h3 id="creating-native">Creating the Renderscript file</h3>
-
- <p>Your Renderscript code resides in <code>.rs</code> and <code>.rsh</code> (headers) files in the
- <code>&lt;project_root&gt;/src/</code> directory. This code contains the logic to render your
- graphics and declares all other necessary items such as variables, structs,
- and pointers. Every graphics <code>.rs</code> file generally contains the following items:</p>
-
- <ul>
- <li>A pragma declaration (<code>#pragma rs java_package_name(<em>package.name</em>)</code>) that declares
- the package name of the <code>.java</code> reflection of this Renderscript.</li>
-
- <li>A pragma declaration (<code>#pragma version(1)</code>) that declares the version of Renderscript that
- you are using (1 is the only value for now).</li>
-
- <li>A <code>#include "rs_graphics.rsh"</code> declaration.</li>
-
- <li>A <code>root()</code> function. This is the main worker function for your Renderscript and
- calls Renderscript graphics functions to render scenes. This function is called every time a
- frame refresh occurs, which is specified as its return value. A <code>0</code> (zero) specified for
- the return value says to only render the frame when a property of the scene that you are
- rendering changes. A non-zero positive integer specifies the refresh rate of the frame in
- milliseconds.
-
- <p class="note"><strong>Note:</strong> The Renderscript runtime makes its best effort to
- refresh the frame at the specified rate. For example, if you are creating a live wallpaper
- and set the return value to 20, the Renderscript runtime renders the wallpaper at 50fps if it has just
- enough or more resources to do so. It renders as fast as it can if not enough resources
- are available.</p>
-
- <p>For more information on using the Renderscript graphics functions, see the <a href=
- "#drawing">Drawing</a> section.</p>
- </li>
-
- <li>An <code>init()</code> function. This allows you to do initialization of your
- Renderscript before the <code>root()</code> function runs, such as assigning values to variables. This
- function runs once and is called automatically when the Renderscript starts, before anything
- else in your Renderscript. Creating this function is optional.</li>
-
- <li>Any variables, pointers, and structures that you wish to use in your Renderscript code (can
- be declared in <code>.rsh</code> files if desired)</li>
- </ul>
-
- <p>The following code shows how the <code>fountain.rs</code> file is implemented:</p>
- <pre>
-#pragma version(1)
-
-// Tell which java package name the reflected files should belong to
-#pragma rs java_package_name(com.example.android.rs.fountain)
-
-//declare shader binding
-#pragma stateFragment(parent)
-
-// header with graphics APIs, must include explicitly
-#include "rs_graphics.rsh"
-
-static int newPart = 0;
-
-// the mesh to render
-rs_mesh partMesh;
-
-// the point representing where a particle is rendered
-typedef struct __attribute__((packed, aligned(4))) Point {
- float2 delta;
- float2 position;
- uchar4 color;
-} Point_t;
-Point_t *point;
-
-// main worker function that renders particles onto the screen
-int root() {
- float dt = min(rsGetDt(), 0.1f);
- rsgClearColor(0.f, 0.f, 0.f, 1.f);
- const float height = rsgGetHeight();
- const int size = rsAllocationGetDimX(rsGetAllocation(point));
- float dy2 = dt * (10.f);
- Point_t * p = point;
- for (int ct=0; ct &lt; size; ct++) {
- p-&gt;delta.y += dy2;
- p-&gt;position += p-&gt;delta;
- if ((p-&gt;position.y &gt; height) &amp;&amp; (p-&gt;delta.y &gt; 0)) {
- p-&gt;delta.y *= -0.3f;
- }
- p++;
- }
-
- rsgDrawMesh(partMesh);
- return 1;
-}
-
-// adds particles to the screen to render
-static float4 partColor[10];
-void addParticles(int rate, float x, float y, int index, bool newColor)
-{
- if (newColor) {
- partColor[index].x = rsRand(0.5f, 1.0f);
- partColor[index].y = rsRand(1.0f);
- partColor[index].z = rsRand(1.0f);
- }
- float rMax = ((float)rate) * 0.02f;
- int size = rsAllocationGetDimX(rsGetAllocation(point));
- uchar4 c = rsPackColorTo8888(partColor[index]);
-
- Point_t * np = &amp;point[newPart];
- float2 p = {x, y};
- while (rate--) {
- float angle = rsRand(3.14f * 2.f);
- float len = rsRand(rMax);
- np-&gt;delta.x = len * sin(angle);
- np-&gt;delta.y = len * cos(angle);
- np-&gt;position = p;
- np-&gt;color = c;
- newPart++;
- np++;
- if (newPart &gt;= size) {
- newPart = 0;
- np = &amp;point[newPart];
- }
- }
-}
-</pre>
-
- <h3 id="creating-entry">Creating the Renderscript entry point class</h3>
-
- <p>When you create a Renderscript (<code>.rs</code>) file, it is helpful to create a
- corresponding Android framework class that is an entry point into the <code>.rs</code> file.
- The most important thing this class does is receive a {@link android.renderscript.RenderScriptGL} rendering context
- object from the <a href="#creating-view">view class</a> and binds the actual Renderscript
- code to the rendering context. This notifies your view class of the code that it needs
- to render graphics.
- </p>
-
- <p>In addition, this class should contain all of the things needed to set up Renderscript.
- Some important things that you need to do in this class are:</p>
-
- <ul>
- <li>Create a Renderscript object
- <code>ScriptC_<em>rs_filename</em></code>. The Renderscript object is attached to the Renderscript bytecode, which is platform-independent and
- gets compiled on the device when the Renderscript application runs. The bytecode is referenced
- as a raw resource and is passed into the constructor for the Renderscript object.
- For example, this is how the <a href="{@docRoot}resources/samples/RenderScript/Fountain/index.html">Fountain</a>
- sample creates the Renderscript object:
- <pre>
- RenderScriptGL rs; //obtained from the view class
- Resources res; //obtained from the view class
- ...
- ScriptC_fountain mScript = new ScriptC_fountain(mRS, mRes, R.raw.fountain);
- </pre>
- </li>
- <li>Allocate any necessary memory and bind it to your Renderscript code via the Renderscript object.</li>
- <li>Build any necessary meshes and bind them to the Renderscript code via the Renderscript object.</li>
- <li>Create any necessary programs and bind them to the Renderscript code via the Renderscript object.</li>
- </ul>
-
- <p>The following code shows how the <a href=
- "{@docRoot}resources/samples/RenderScript/Fountain/src/com/example/android/rs/fountain/FountainRS.html">
- FountainRS</a> class is implemented:</p>
- <pre>
-package com.example.android.rs.fountain;
-
-import android.content.res.Resources;
-import android.renderscript.*;
-import android.util.Log;
-
-public class FountainRS {
- public static final int PART_COUNT = 50000;
-
- public FountainRS() {
- }
-
- /**
- * This provides us with the Renderscript context and resources
- * that allow us to create the Renderscript object
- */
- private Resources mRes;
- private RenderScriptGL mRS;
-
- // Renderscript object
- private ScriptC_fountain mScript;
-
- // Called by the view class to initialize the Renderscript context and renderer
- public void init(RenderScriptGL rs, Resources res) {
- mRS = rs;
- mRes = res;
-
- /**
- * Create a shader and bind to the Renderscript context
- */
- ProgramFragmentFixedFunction.Builder pfb = new ProgramFragmentFixedFunction.Builder(rs);
- pfb.setVaryingColor(true);
- rs.bindProgramFragment(pfb.create());
-
- /**
- * Allocate memory for the particles to render and create the mesh to draw
- */
- ScriptField_Point points = new ScriptField_Point(mRS, PART_COUNT);
- Mesh.AllocationBuilder smb = new Mesh.AllocationBuilder(mRS);
- smb.addVertexAllocation(points.getAllocation());
- smb.addIndexSetType(Mesh.Primitive.POINT);
- Mesh sm = smb.create();
-
- /**
- * Create and bind the Renderscript object to the Renderscript context
- */
- mScript = new ScriptC_fountain(mRS, mRes, R.raw.fountain);
- mScript.set_partMesh(sm);
- mScript.bind_point(points);
- mRS.bindRootScript(mScript);
- }
-
- boolean holdingColor[] = new boolean[10];
-
- /**
- * Calls Renderscript functions (invoke_addParticles)
- * via the Renderscript object to add particles to render
- * based on where a user touches the screen.
- */
- public void newTouchPosition(float x, float y, float pressure, int id) {
- if (id &gt;= holdingColor.length) {
- return;
- }
- int rate = (int)(pressure * pressure * 500.f);
- if (rate &gt; 500) {
- rate = 500;
- }
- if (rate &gt; 0) {
- mScript.invoke_addParticles(rate, x, y, id, !holdingColor[id]);
- holdingColor[id] = true;
- } else {
- holdingColor[id] = false;
- }
-
- }
-}
-</pre>
-
-
- <h3 id="creating-view">Creating the view class</h3>
-
-
- <p>To display graphics, you need a view to render on. Create a class that extends {@link
- android.renderscript.RSSurfaceView} or {@link android.renderscript.RSTextureView}. This class
- allows you to create a {@link android.renderscript.RenderScriptGL} context object by calling and
- pass it to the Rendscript entry point class to bind the two. Once bound, the content is aware
- of the code that it needs to use to render graphics with. If your Renderscript code
- depends on any type of information that the view is aware of, such as touches from the user,
- you can also use this class to relay that information to the Renderscript entry point class.
- The following code shows how the <code>FountainView</code> class is implemented:</p>
- <pre>
-package com.example.android.rs.fountain;
-
-import android.renderscript.RSTextureView;
-import android.renderscript.RenderScriptGL;
-import android.content.Context;
-import android.view.MotionEvent;
-
-public class FountainView extends RSTextureView {
-
- public FountainView(Context context) {
- super(context);
- }
- // Renderscript context
- private RenderScriptGL mRS;
- // Renderscript entry point object that calls Renderscript code
- private FountainRS mRender;
-
- /**
- * Create Renderscript context and initialize Renderscript entry point
- */
- &#064;Override
- protected void onAttachedToWindow() {
- super.onAttachedToWindow();
- android.util.Log.e("rs", "onAttachedToWindow");
- if (mRS == null) {
- RenderScriptGL.SurfaceConfig sc = new RenderScriptGL.SurfaceConfig();
- mRS = createRenderScriptGL(sc);
- mRender = new FountainRS();
- mRender.init(mRS, getResources());
- }
- }
-
- &#064;Override
- protected void onDetachedFromWindow() {
- super.onDetachedFromWindow();
- android.util.Log.e("rs", "onDetachedFromWindow");
- if (mRS != null) {
- mRS = null;
- destroyRenderScriptGL();
- }
- }
-
-
- /**
- * Use callbacks to relay data to Renderscript entry point class
- */
- &#064;Override
- public boolean onTouchEvent(MotionEvent ev)
- {
- int act = ev.getActionMasked();
- if (act == ev.ACTION_UP) {
- mRender.newTouchPosition(0, 0, 0, ev.getPointerId(0));
- return false;
- } else if (act == MotionEvent.ACTION_POINTER_UP) {
- // only one pointer going up, we can get the index like this
- int pointerIndex = ev.getActionIndex();
- int pointerId = ev.getPointerId(pointerIndex);
- mRender.newTouchPosition(0, 0, 0, pointerId);
- }
- int count = ev.getHistorySize();
- int pcount = ev.getPointerCount();
-
- for (int p=0; p &lt; pcount; p++) {
- int id = ev.getPointerId(p);
- mRender.newTouchPosition(ev.getX(p),
- ev.getY(p),
- ev.getPressure(p),
- id);
-
- for (int i=0; i &lt; count; i++) {
- mRender.newTouchPosition(ev.getHistoricalX(p, i),
- ev.getHistoricalY(p, i),
- ev.getHistoricalPressure(p, i),
- id);
- }
- }
- return true;
- }
-}
-</pre>
-
- <h3 id="creating-activity">Creating the activity class</h3>
-
- <p>Applications that use Renderscript still behave like normal Android applications, so you
- need an activity class that handles activity lifecycle callback events appropriately. The activity class
- also sets your {@link android.renderscript.RSSurfaceView} view class to be the main content view of the
- activity or uses your {@link android.renderscript.RSTextureView}
- in a {@link android.view.ViewGroup} alongside other views.</p>
-
- <p>The following code shows how the <a href="{@docRoot}resources/samples/RenderScript/Fountain/index.html">Fountain</a>
- sample declares its activity class:</p>
- <pre>
-package com.example.android.rs.fountain;
-
-import android.app.Activity;
-import android.os.Bundle;
-import android.util.Log;
-
-public class Fountain extends Activity {
-
- private static final String LOG_TAG = "libRS_jni";
- private static final boolean DEBUG = false;
- private static final boolean LOG_ENABLED = false;
-
- private FountainView mView;
-
- &#064;Override
- public void onCreate(Bundle icicle) {
- super.onCreate(icicle);
-
- // Create our Preview view and set it as
- // the content of our activity
- mView = new FountainView(this);
- setContentView(mView);
- }
-
- &#064;Override
- protected void onResume() {
- Log.e("rs", "onResume");
-
- // Ideally a game should implement onResume() and onPause()
- // to take appropriate action when the activity looses focus
- super.onResume();
- mView.resume();
- }
-
- &#064;Override
- protected void onPause() {
- Log.e("rs", "onPause");
-
- // Ideally a game should implement onResume() and onPause()
- // to take appropriate action when the activity looses focus
- super.onPause();
- mView.pause();
-
- }
-
- static void log(String message) {
- if (LOG_ENABLED) {
- Log.v(LOG_TAG, message);
- }
- }
-}
-</pre>
-
-<p>Now that you have an idea of what is involved in a Renderscript graphics application, you can
-start building your own. It might be easiest to begin with one of the
-<a href="{@docRoot}resources/samples/RenderScript/index.html">Renderscript samples</a> as a starting
-point if this is your first time using Renderscript.</p>
-
- <h2 id="drawing">Drawing</h2>
- <p>The following sections describe how to use the graphics functions to draw with Renderscript.</p>
-
- <h3 id="drawing-rsg">Simple drawing</h3>
-
- <p>The native Renderscript APIs provide a few convenient functions to easily draw a polygon or text to
- the screen. You call these in your <code>root()</code> function to have them render to the {@link
- android.renderscript.RSSurfaceView} or {@link android.renderscript.RSTextureView}. These functions are
- available for simple drawing and should not be used for complex graphics rendering:</p>
-
- <ul>
- <li><code>rsgDrawRect()</code>: Sets up a mesh and draws a rectangle to the screen. It uses the
- top left vertex and bottom right vertex of the rectangle to draw.</li>
-
- <li><code>rsgDrawQuad()</code>: Sets up a mesh and draws a quadrilateral to the screen.</li>
-
- <li><code>rsgDrawQuadTexCoords()</code>: Sets up a mesh and draws a quadrilateral to the screen
- using the provided coordinates of a texture.</li>
-
- <li><code>rsgDrawText()</code>: Draws specified text to the screen. Use <code>rsgFontColor()</code>
- to set the color of the text.</li>
- </ul>
-
- <h3 id="drawing-mesh">Drawing with a mesh</h3>
-
- <p>When you want to render complex scenes to the screen, instantiate a {@link
- android.renderscript.Mesh} and draw it with <code>rsgDrawMesh()</code>. A {@link
- android.renderscript.Mesh} is a collection of allocations that represent vertex data (positions,
- normals, texture coordinates) and index data that provides information on how to draw triangles
- and lines with the provided vertex data. You can build a Mesh in three different ways:</p>
-
- <ul>
- <li>Build the mesh with the {@link android.renderscript.Mesh.TriangleMeshBuilder} class, which
- allows you to specify a set of vertices and indices for each triangle that you want to draw.</li>
-
- <li>Build the mesh using an {@link android.renderscript.Allocation} or a set of {@link
- android.renderscript.Allocation}s with the {@link android.renderscript.Mesh.AllocationBuilder}
- class. This approach allows you to build a mesh with vertices already stored in memory, which allows you
- to specify the vertices in Renderscript or Android framework code.</li>
-
- <li>Build the mesh with the {@link android.renderscript.Mesh.Builder} class. You should use
- this convenience method when you know the data types you want to use to build your mesh, but
- don't want to make separate memory allocations like with {@link
- android.renderscript.Mesh.AllocationBuilder}. You can specify the types that you want and this
- mesh builder automatically creates the memory allocations for you.</li>
- </ul>
-
- <p>To create a mesh using the {@link android.renderscript.Mesh.TriangleMeshBuilder}, you need to
- supply it with a set of vertices and the indices for the vertices that comprise the triangle. For
- example, the following code specifies three vertices, which are added to an internal array,
- indexed in the order they were added. The call to {@link
- android.renderscript.Mesh.TriangleMeshBuilder#addTriangle addTriangle()} draws the triangle with
- vertex 0, 1, and 2 (the vertices are drawn counter-clockwise).</p>
- <pre>
-int float2VtxSize = 2;
-Mesh.TriangleMeshBuilder triangles = new Mesh.TriangleMeshBuilder(renderscriptGL,
-float2VtxSize, Mesh.TriangleMeshBuilder.COLOR);
-triangles.addVertex(300.f, 300.f);
-triangles.addVertex(150.f, 450.f);
-triangles.addVertex(450.f, 450.f);
-triangles.addTriangle(0 , 1, 2);
-Mesh smP = triangle.create(true);
-script.set_mesh(smP);
-</pre>
-
- <p>To draw a mesh using the {@link android.renderscript.Mesh.AllocationBuilder}, you need to
- supply it with one or more allocations that contain the vertex data:</p>
- <pre>
-Allocation vertices;
-
-...
-Mesh.AllocationBuilder triangle = new Mesh.AllocationBuilder(mRS);
-smb.addVertexAllocation(vertices.getAllocation());
-smb.addIndexSetType(Mesh.Primitive.TRIANGLE);
-Mesh smP = smb.create();
-script.set_mesh(smP);
-</pre>
-
- <p>In your Renderscript code, draw the built mesh to the screen:</p>
- <pre>
-rs_mesh mesh;
-...
-
-int root(){
-...
-rsgDrawMesh(mesh);
-...
-return 0; //specify a non zero, positive integer to specify the frame refresh.
- //0 refreshes the frame only when the mesh changes.
-}
-</pre>
-
- <h2 id="shader">Programs</h2>
-
- <p>You can attach four program objects to the {@link android.renderscript.RenderScriptGL} context
- to customize the rendering pipeline. For example, you can create vertex and fragment shaders in
- GLSL or build a raster program object that controls culling. The four programs mirror a
- traditional graphical rendering pipeline:</p>
-
- <table>
- <tr>
- <th>Android Object Type</th>
-
- <th>Renderscript Native Type</th>
-
- <th>Description</th>
- </tr>
-
- <tr>
- <td>{@link android.renderscript.ProgramVertex}</td>
-
- <td>rs_program_vertex</td>
-
- <td>
- <p>The Renderscript vertex program, also known as a vertex shader, describes the stage in
- the graphics pipeline responsible for manipulating geometric data in a user-defined way.
- The object is constructed by providing Renderscript with the following data:</p>
-
- <ul>
- <li>An {@link android.renderscript.Element} describing its varying inputs or attributes</li>
-
- <li>GLSL shader string that defines the body of the program</li>
-
- <li>a {@link android.renderscript.Type} that describes the layout of an
- Allocation containing constant or uniform inputs</li>
- </ul>
-
- <p>Once the program is created, bind it to the {@link android.renderscript.RenderScriptGL}
- graphics context by calling {@link android.renderscript.RenderScriptGL#bindProgramVertex
- bindProgramVertex()}. It is then used for all subsequent draw calls until you bind a new
- program. If the program has constant inputs, the user needs to bind an allocation
- containing those inputs. The allocation's type must match the one provided during creation.
- </p>
-
- <p>The Renderscript runtime then does all the necessary plumbing to send those constants to
- the graphics hardware. Varying inputs to the shader, such as position, normal, and texture
- coordinates are matched by name between the input {@link android.renderscript.Element}
- and the mesh object that is being drawn. The signatures don't have to be exact or in any
- strict order. As long as the input name in the shader matches a channel name and size
- available on the mesh, the Renderscript runtime handles connecting the two. Unlike OpenGL
- there is no need to link the vertex and fragment programs.</p>
-
- <p>To bind shader constants to the program, declare a <code>struct</code> that contains the necessary
- shader constants in your Renderscript code. This <code>struct</code> is generated into a
- reflected class that you can use as a constant input element during the program's creation.
- It is an easy way to create an instance of this <code>struct</code> as an allocation. You would then
- bind this {@link android.renderscript.Allocation} to the program and the
- Renderscript runtime sends the data that is contained in the <code>struct</code> to the hardware
- when necessary. To update shader constants, you change the values in the
- {@link android.renderscript.Allocation} and notify the Renderscript
- code of the change.</p>
-
- <p>The {@link android.renderscript.ProgramVertexFixedFunction.Builder} class also
- lets you build a simple vertex shader without writing GLSL code.
- </p>
- </td>
- </tr>
-
- <tr>
- <td>{@link android.renderscript.ProgramFragment}</td>
-
- <td>rs_program_fragment</td>
-
- <td>
- <p>The Renderscript fragment program, also known as a fragment shader, is responsible for
- manipulating pixel data in a user-defined way. It's constructed from a GLSL shader string
- containing the program body, texture inputs, and a {@link android.renderscript.Type}
- object that describes the constants
- used by the program. Like the vertex programs, when an {@link android.renderscript.Allocation}
- with constant input
- values is bound to the shader, its values are sent to the graphics program automatically.
- Note that the values inside the {@link android.renderscript.Allocation} are not explicitly tracked.
- If they change between two draw calls using the same program object, notify the runtime of that change by
- calling <code>rsgAllocationSyncAll()</code>, so it can send the new values to hardware. Communication
- between the vertex and fragment programs is handled internally in the GLSL code. For
- example, if the fragment program is expecting a varying input called <code>varTex0</code>, the GLSL code
- inside the program vertex must provide it.</p>
-
- <p>To bind shader constructs to the program, declare a <code>struct</code> that contains the necessary
- shader constants in your Renderscript code. This <code>struct</code> is generated into a
- reflected class that you can use as a constant input element during the program's creation.
- It is an easy way to create an instance of this <code>struct</code> as an allocation. You would then
- bind this {@link android.renderscript.Allocation} to the program and the
- Renderscript runtime sends the data that is contained in the <code>struct</code> to the hardware
- when necessary. To update shader constants, you change the values in the
- {@link android.renderscript.Allocation} and notify the Renderscript
- code of the change.</p>
-
- <p>The {@link android.renderscript.ProgramFragmentFixedFunction.Builder} class also
- lets you build a simple fragment shader without writing GLSL code.
- </p>
- </td>
- </tr>
-
- <tr>
- <td>{@link android.renderscript.ProgramStore}</td>
-
- <td>rs_program_store</td>
-
- <td>The Renderscript store program contains a set of parameters that control how the graphics
- hardware writes to the framebuffer. It could be used to enable and disable depth writes and
- testing, setup various blending modes for effects like transparency and define write masks
- for color components.</td>
- </tr>
-
- <tr>
- <td>{@link android.renderscript.ProgramRaster}</td>
-
- <td>rs_program_raster</td>
-
- <td>The Renderscript raster program is primarily used to specify whether point sprites are enabled and to
- control the culling mode. By default back faces are culled.</td>
- </tr>
- </table>
-
- <p>The following example defines a vertex shader in GLSL and binds it to a Renderscript context object:</p>
- <pre>
- private RenderScriptGL glRenderer; //rendering context
- private ScriptField_Point mPoints; //vertices
- private ScriptField_VpConsts mVpConsts; //shader constants
-
- ...
-
- ProgramVertex.Builder sb = new ProgramVertex.Builder(glRenderer);
- String t = "varying vec4 varColor;\n" +
- "void main() {\n" +
- " vec4 pos = vec4(0.0, 0.0, 0.0, 1.0);\n" +
- " pos.xy = ATTRIB_position;\n" +
- " gl_Position = UNI_MVP * pos;\n" +
- " varColor = vec4(1.0, 1.0, 1.0, 1.0);\n" +
- " gl_PointSize = ATTRIB_size;\n" +
- "}\n";
- sb.setShader(t);
- sb.addConstant(mVpConsts.getType());
- sb.addInput(mPoints.getElement());
- ProgramVertex pvs = sb.create();
- pvs.bindConstants(mVpConsts.getAllocation(), 0);
- glRenderer.bindProgramVertex(pvs);
-</pre>
-
-
- <p>The <a href=
- "{@docRoot}resources/samples/RenderScript/MiscSamples/src/com/example/android/rs/miscsamples/RsRenderStatesRS.html">
- RsRenderStatesRS</a> sample has many examples on how to create a shader without writing GLSL.</p>
-
- <h3 id="shader-bindings">Program bindings</h3>
-
- <p>You can also declare four pragmas that control default program bindings to the {@link
- android.renderscript.RenderScriptGL} context when the script is executing:</p>
-
- <ul>
- <li><code>stateVertex</code></li>
-
- <li><code>stateFragment</code></li>
-
- <li><code>stateRaster</code></li>
-
- <li><code>stateStore</code></li>
- </ul>
-
- <p>The possible values for each pragma are <code>parent</code> or <code>default</code>. Using
- <code>default</code> binds the shaders to the graphical context with the system defaults.</p>
-
- <p>Using <code>parent</code> binds the shaders in the same manner as it is bound in the calling
- script. If this is the root script, the parent state is taken from the bind points that are set
- by the {@link android.renderscript.RenderScriptGL} bind methods.</p>
-
- <p>For example, you can define this at the top of your graphics Renderscript code to have
- the vertex and store programs inherent the bind properties from their parent scripts:</p>
- <pre>
-#pragma stateVertex(parent)
-#pragma stateStore(parent)
-</pre>
-
- <h3 id="shader-sampler">Defining a sampler</h3>
-
- <p>A {@link android.renderscript.Sampler} object defines how data is extracted from textures.
- Samplers are bound to a {@link android.renderscript.ProgramFragment} alongside the texture
- whose sampling they control. These
- objects are used to specify such things as edge clamping behavior, whether mip-maps are used, and
- the amount of anisotropy required. There might be situations where hardware does not support the
- desired behavior of the sampler. In these cases, the Renderscript runtime attempts to provide the
- closest possible approximation. For example, the user requested 16x anisotropy, but only 8x was
- set because it's the best available on the hardware.</p>
-
- <p>The <a href=
- "{@docRoot}resources/samples/RenderScript/MiscSamples/src/com/example/android/rs/miscsamples/RsRenderStatesRS.html">
- RsRenderStatesRS</a> sample has many examples on how to create a sampler and bind it to a
- Fragment program.</p>
-
-
-
-<h2 id="fbo">Rendering to a Framebuffer Object</h2>
-
-<p>Framebuffer objects allow you to render offscreen instead of in the default onscreen
-framebuffer. This approach might be useful for situations where you need to post-process a texture before
-rendering it to the screen, or when you want to composite two scenes in one such as rendering a rear-view
-mirror of a car. There are two buffers associated with a framebuffer object: a color buffer
-and a depth buffer. The color buffer (required) contains the actual pixel data of the scene
-that you are rendering, and the depth buffer (optional) contains the values necessary to figure
-out what vertices are drawn depending on their z-values.</p>
-
-<p>In general, you need to do the following to render to a framebuffer object:</p>
-
-<ul>
- <li>Create {@link android.renderscript.Allocation} objects for the color buffer and
- depth buffer (if needed). Specify the {@link
- android.renderscript.Allocation#USAGE_GRAPHICS_RENDER_TARGET} usage attribute for these
- allocations to notify the Renderscript runtime to use these allocations for the framebuffer
- object. For the color buffer allocation, you most likely need to declare the {@link
- android.renderscript.Allocation#USAGE_GRAPHICS_TEXTURE} usage attribute
- to use the color buffer as a texture, which is the most common use of the framebuffer object.</li>
-
- <li>Tell the Renderscript runtime to render to the framebuffer object instead of the default
- framebuffer by calling <code>rsgBindColorTarget()</code> and passing it the color buffer
- allocation. If applicable, call <code>rsgBindDepthTarget()</code> passing in the depth buffer
- allocation as well.</li>
-
- <li>Render your scene normally with the <code>rsgDraw</code> functions. The scene will be
- rendered into the color buffer instead of the default onscreen framebuffer.</li>
-
- <li>When done, tell the Renderscript runtime stop rendering to the color buffer and back
- to the default framebuffer by calling <code>rsgClearAllRenderTargets()</code>.</li>
-
- <li>Create a fragment shader and bind a the color buffer to it as a texture.</li>
-
- <li>Render your scene to the default framebuffer. The texture will be used according
- to the way you setup your fragment shader.</li>
-</ul>
-
-<p>The following example shows you how to render to a framebuffer object by modifying the
-<a href="{@docRoot}guide/resources/renderscript/Fountain/">Fountain</a> Renderscript sample. The end
-result is the <a href="{@docRoot}guide/resources/renderscript/FountainFBO/">FountainFBO</a> sample.
-The modifications render the exact same scene into a framebuffer object as it does the default
-framebuffer. The framebuffer object is then rendered into the default framebuffer in a small
-area at the top left corner of the screen.</p>
-
-<ol>
- <li>Modify <code>fountain.rs</code> and add the following global variables. This creates setter
- methods when this file is reflected into a <code>.java</code> file, allowing you to allocate
- memory in your Android framework code and binding it to the Renderscript runtime.
-<pre>
-//allocation for color buffer
-rs_allocation gColorBuffer;
-//fragment shader for rendering without a texture (used for rendering to framebuffer object)
-rs_program_fragment gProgramFragment;
-//fragment shader for rendering with a texture (used for rendering to default framebuffer)
-rs_program_fragment gTextureProgramFragment;
-</pre>
- </li>
-
- <li>Modify the root function of <code>fountain.rs</code> to look like the following code. The
- modifications are commented:
-<pre>
-int root() {
- float dt = min(rsGetDt(), 0.1f);
- rsgClearColor(0.f, 0.f, 0.f, 1.f);
- const float height = rsgGetHeight();
- const int size = rsAllocationGetDimX(rsGetAllocation(point));
- float dy2 = dt * (10.f);
- Point_t * p = point;
- for (int ct=0; ct < size; ct++) {
- p->delta.y += dy2;
- p->position += p->delta;
- if ((p->position.y > height) && (p->delta.y > 0)) {
- p->delta.y *= -0.3f;
- }
- p++;
- }
- //Tell Renderscript runtime to render to the frame buffer object
- rsgBindColorTarget(gColorBuffer, 0);
- //Begin rendering on a white background
- rsgClearColor(1.f, 1.f, 1.f, 1.f);
- rsgDrawMesh(partMesh);
-
- //When done, tell Renderscript runtime to stop rendering to framebuffer object
- rsgClearAllRenderTargets();
-
- //Bind a new fragment shader that declares the framebuffer object to be used as a texture
- rsgBindProgramFragment(gTextureProgramFragment);
-
- //Bind the framebuffer object to the fragment shader at slot 0 as a texture
- rsgBindTexture(gTextureProgramFragment, 0, gColorBuffer);
- //Draw a quad using the framebuffer object as the texture
- float startX = 10, startY = 10;
- float s = 256;
- rsgDrawQuadTexCoords(startX, startY, 0, 0, 1,
- startX, startY + s, 0, 0, 0,
- startX + s, startY + s, 0, 1, 0,
- startX + s, startY, 0, 1, 1);
-
- //Rebind the original fragment shader to render as normal
- rsgBindProgramFragment(gProgramFragment);
-
- //Render the main scene
- rsgDrawMesh(partMesh);
-
- return 1;
-}
-</pre>
- </li>
-
- <li>In the <code>FountainRS.java</code> file, modify the <code>init()</code> method to look
- like the following code. The modifications are commented:
-
-<pre>
-/* Add necessary members */
-private ScriptC_fountainfbo mScript;
-private Allocation mColorBuffer;
-private ProgramFragment mProgramFragment;
-private ProgramFragment mTextureProgramFragment;
-
-public void init(RenderScriptGL rs, Resources res) {
- mRS = rs;
- mRes = res;
-
- ScriptField_Point points = new ScriptField_Point(mRS, PART_COUNT);
-
- Mesh.AllocationBuilder smb = new Mesh.AllocationBuilder(mRS);
- smb.addVertexAllocation(points.getAllocation());
- smb.addIndexSetType(Mesh.Primitive.POINT);
- Mesh sm = smb.create();
-
- mScript = new ScriptC_fountainfbo(mRS, mRes, R.raw.fountainfbo);
- mScript.set_partMesh(sm);
- mScript.bind_point(points);
-
- ProgramFragmentFixedFunction.Builder pfb = new ProgramFragmentFixedFunction.Builder(rs);
- pfb.setVaryingColor(true);
- mProgramFragment = pfb.create();
- mScript.set_gProgramFragment(mProgramFragment);
-
- /* Second fragment shader to use a texture (framebuffer object) to draw with */
- pfb.setTexture(ProgramFragmentFixedFunction.Builder.EnvMode.REPLACE,
- ProgramFragmentFixedFunction.Builder.Format.RGBA, 0);
-
- /* Set the fragment shader in the Renderscript runtime */
- mTextureProgramFragment = pfb.create();
- mScript.set_gTextureProgramFragment(mTextureProgramFragment);
-
- /* Create the allocation for the color buffer */
- Type.Builder colorBuilder = new Type.Builder(mRS, Element.RGBA_8888(mRS));
- colorBuilder.setX(256).setY(256);
- mColorBuffer = Allocation.createTyped(mRS, colorBuilder.create(),
- Allocation.USAGE_GRAPHICS_TEXTURE |
- Allocation.USAGE_GRAPHICS_RENDER_TARGET);
-
- /* Set the allocation in the Renderscript runtime */
- mScript.set_gColorBuffer(mColorBuffer);
-
- mRS.bindRootScript(mScript);
-}
-</pre>
-
-<p class="note"><strong>Note:</strong> This sample doesn't use a depth buffer, but the following code
-shows you how to declare an example depth buffer if you need to use
-one for your application. The depth buffer must have the same dimensions as the color buffer:
-
-<pre>
-Allocation mDepthBuffer;
-
-...
-
-Type.Builder b = new Type.Builder(mRS, Element.createPixel(mRS, DataType.UNSIGNED_16,
- DataKind.PIXEL_DEPTH));
-b.setX(256).setY(256);
-mDepthBuffer = Allocation.createTyped(mRS, b.create(),
-Allocation.USAGE_GRAPHICS_RENDER_TARGET);
-
-</pre>
-</p>
-</li>
-
- <li>Run and use the sample. The smaller, white quad on the top-left corner is using the
- framebuffer object as a texture, which renders the same scene as the main rendering.</li>
-</ol>