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Diffstat (limited to 'docs/html/guide/topics/graphics/opengl.jd')
| -rw-r--r-- | docs/html/guide/topics/graphics/opengl.jd | 54 |
1 files changed, 33 insertions, 21 deletions
diff --git a/docs/html/guide/topics/graphics/opengl.jd b/docs/html/guide/topics/graphics/opengl.jd index 2edc63d..b750858 100644 --- a/docs/html/guide/topics/graphics/opengl.jd +++ b/docs/html/guide/topics/graphics/opengl.jd @@ -14,7 +14,7 @@ parent.link=index.html </ol> <li><a href="#manifest">Declaring OpenGL Requirements</a></li> </li> - <li><a href="#coordinate-mapping">Coordinate Mapping for Drawn Objects</a> + <li><a href="#coordinate-mapping">Mapping Coordinates for Drawn Objects</a> <ol> <li><a href="#proj-es1">Projection and camera in ES 1.0</a></li> <li><a href="#proj-es1">Projection and camera in ES 2.0</a></li> @@ -197,9 +197,9 @@ shown below. installed on devices that do not support OpenGL ES 2.0.</p> </li> <li><strong>Texture compression requirements</strong> - If your application uses texture -compression formats that are not supported by all devices, you must declare them in your manifest -file using <a href="{@docRoot}guide/topics/manifest/supports-gl-texture-element.html"> -{@code <supports-gl-texture>}</a>. For more information about available texture compression +compression formats, you must declare the formats your application supports in your manifest file +using <a href="{@docRoot}guide/topics/manifest/supports-gl-texture-element.html">{@code +<supports-gl-texture>}</a>. For more information about available texture compression formats, see <a href="#textures">Texture compression support</a>. <p>Declaring texture compression requirements in your manifest hides your application from users @@ -212,7 +212,7 @@ Android Market and texture compression filtering</a> section of the {@code </ul> -<h2 id="coordinate-mapping">Coordinate Mapping for Drawn Objects</h2> +<h2 id="coordinate-mapping">Mapping Coordinates for Drawn Objects</h2> <p>One of the basic problems in displaying graphics on Android devices is that their screens can vary in size and shape. OpenGL assumes a square, uniform coordinate system and, by default, happily @@ -241,9 +241,11 @@ adding them to the OpenGL environment.</p> <ol> <li><strong>Projection matrix</strong> - Create a projection matrix using the geometry of the device screen in order to recalculate object coordinates so they are drawn with correct proportions. -The following example code demonstrates how to modify the {@code onSurfaceChanged()} method of a -{@link android.opengl.GLSurfaceView.Renderer} implementation to create a projection matrix based on -the screen's aspect ratio and apply it to the OpenGL rendering environment. +The following example code demonstrates how to modify the {@link +android.opengl.GLSurfaceView.Renderer#onSurfaceChanged(javax.microedition.khronos.opengles.GL10, +int, int) onSurfaceChanged()} method of a {@link android.opengl.GLSurfaceView.Renderer} +implementation to create a projection matrix based on the screen's aspect ratio and apply it to the +OpenGL rendering environment. <pre> public void onSurfaceChanged(GL10 gl, int width, int height) { @@ -260,11 +262,13 @@ the screen's aspect ratio and apply it to the OpenGL rendering environment. <li><strong>Camera transformation matrix</strong> - Once you have adjusted the coordinate system using a projection matrix, you must also apply a camera view. The following example code shows how -to modify the {@code onDrawFrame()} method of a {@link android.opengl.GLSurfaceView.Renderer} -implementation to apply a model view and use the {@link -android.opengl.GLU#gluLookAt(javax.microedition.khronos.opengles.GL10, float, float, float, float, -float, float, float, float, float) GLU.gluLookAt()} utility to create a viewing tranformation which -simulates a camera position. +to modify the {@link +android.opengl.GLSurfaceView.Renderer#onDrawFrame(javax.microedition.khronos.opengles.GL10) +onDrawFrame()} method of a {@link android.opengl.GLSurfaceView.Renderer} +implementation to apply a model view and use the +{@link android.opengl.GLU#gluLookAt(javax.microedition.khronos.opengles.GL10, float, float, float, +float, float, float, float, float, float) GLU.gluLookAt()} utility to create a viewing tranformation +which simulates a camera position. <pre> public void onDrawFrame(GL10 gl) { @@ -320,8 +324,10 @@ independently.</p> </li> <li><strong>Access the shader matrix</strong> - After creating a hook in your vertex shaders to apply projection and camera view, you can then access that variable to apply projection and -camera viewing matrices. The following code shows how to modify the {@code onSurfaceCreated()} -method of a {@link android.opengl.GLSurfaceView.Renderer} implementation to access the matrix +camera viewing matrices. The following code shows how to modify the {@link +android.opengl.GLSurfaceView.Renderer#onSurfaceCreated(javax.microedition.khronos.opengles.GL10, +javax.microedition.khronos.egl.EGLConfig) onSurfaceCreated()} method of a {@link +android.opengl.GLSurfaceView.Renderer} implementation to access the matrix variable defined in the vertex shader above. <pre> @@ -334,9 +340,13 @@ variable defined in the vertex shader above. </li> <li><strong>Create projection and camera viewing matrices</strong> - Generate the projection and viewing matrices to be applied the graphic objects. The following example code shows how to modify -the {@code onSurfaceCreated()} and {@code onSurfaceChanged()} methods of a {@link -android.opengl.GLSurfaceView.Renderer} implementation to create camera view matrix and a projection -matrix based on the screen aspect ratio of the device. +the {@link +android.opengl.GLSurfaceView.Renderer#onSurfaceCreated(javax.microedition.khronos.opengles.GL10, +javax.microedition.khronos.egl.EGLConfig) onSurfaceCreated()} and {@link +android.opengl.GLSurfaceView.Renderer#onSurfaceChanged(javax.microedition.khronos.opengles.GL10, +int, int) onSurfaceChanged()} methods of a {@link android.opengl.GLSurfaceView.Renderer} +implementation to create camera view matrix and a projection matrix based on the screen aspect ratio +of the device. <pre> public void onSurfaceCreated(GL10 unused, EGLConfig config) { @@ -358,9 +368,11 @@ matrix based on the screen aspect ratio of the device. <li><strong>Apply projection and camera viewing matrices</strong> - To apply the projection and camera view transformations, multiply the matrices together and then set them into the vertex -shader. The following example code shows how modify the {@code onDrawFrame()} method of a {@link -android.opengl.GLSurfaceView.Renderer} implementation to combine the projection matrix and camera -view created in the code above and then apply it to the graphic objects to be rendered by OpenGL. +shader. The following example code shows how modify the {@link +android.opengl.GLSurfaceView.Renderer#onDrawFrame(javax.microedition.khronos.opengles.GL10) +onDrawFrame()} method of a {@link android.opengl.GLSurfaceView.Renderer} implementation to combine +the projection matrix and camera view created in the code above and then apply it to the graphic +objects to be rendered by OpenGL. <pre> public void onDrawFrame(GL10 unused) { |