docs: code fixes for OpenGL ES training
code sample fixes reviewed separately,
see Change-Id: I1d760b75d1f2bfe1ec90c71471867577bd146241
fixing bugs:
b/10798358
b/10796990
b/10603728
b/7962328
Change-Id: I1e0f6668ec8d2b103b88c385f1f067d30ecc7178
diff --git a/docs/downloads/training/OpenGLES.zip b/docs/downloads/training/OpenGLES.zip
index 862ae1f..5bdfee3 100644
--- a/docs/downloads/training/OpenGLES.zip
+++ b/docs/downloads/training/OpenGLES.zip
Binary files differ
diff --git a/docs/html/images/opengl/ogl-triangle-projected.png b/docs/html/images/opengl/ogl-triangle-projected.png
index d10bbdc..4b18b98 100644
--- a/docs/html/images/opengl/ogl-triangle-projected.png
+++ b/docs/html/images/opengl/ogl-triangle-projected.png
Binary files differ
diff --git a/docs/html/images/opengl/ogl-triangle-touch.png b/docs/html/images/opengl/ogl-triangle-touch.png
index 35177a4..8323dd9 100644
--- a/docs/html/images/opengl/ogl-triangle-touch.png
+++ b/docs/html/images/opengl/ogl-triangle-touch.png
Binary files differ
diff --git a/docs/html/images/opengl/ogl-triangle.png b/docs/html/images/opengl/ogl-triangle.png
index 3d4a385..66047ab 100644
--- a/docs/html/images/opengl/ogl-triangle.png
+++ b/docs/html/images/opengl/ogl-triangle.png
Binary files differ
diff --git a/docs/html/training/graphics/opengl/draw.jd b/docs/html/training/graphics/opengl/draw.jd
index 156ff70..ba00627 100644
--- a/docs/html/training/graphics/opengl/draw.jd
+++ b/docs/html/training/graphics/opengl/draw.jd
@@ -122,7 +122,7 @@
get created once and then cached for later use.</p>
<pre>
-public Triangle() {
+public class Triangle() {
...
int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexShaderCode);
diff --git a/docs/html/training/graphics/opengl/environment.jd b/docs/html/training/graphics/opengl/environment.jd
index e1e2c8a..77faabf 100644
--- a/docs/html/training/graphics/opengl/environment.jd
+++ b/docs/html/training/graphics/opengl/environment.jd
@@ -92,7 +92,7 @@
{@link android.opengl.GLSurfaceView} as its primary view:</p>
<pre>
-public class OpenGLES20 extends Activity {
+public class OpenGLES20Activity extends Activity {
private GLSurfaceView mGLView;
@@ -190,11 +190,11 @@
gray background in the {@link android.opengl.GLSurfaceView}:</p>
<pre>
-public class MyGL20Renderer implements GLSurfaceView.Renderer {
+public class MyGLRenderer implements GLSurfaceView.Renderer {
public void onSurfaceCreated(GL10 unused, EGLConfig config) {
// Set the background frame color
- GLES20.glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
+ GLES20.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
}
public void onDrawFrame(GL10 unused) {
diff --git a/docs/html/training/graphics/opengl/motion.jd b/docs/html/training/graphics/opengl/motion.jd
index af70de0..fbcdd7f 100644
--- a/docs/html/training/graphics/opengl/motion.jd
+++ b/docs/html/training/graphics/opengl/motion.jd
@@ -53,16 +53,20 @@
private float[] mRotationMatrix = new float[16];
public void onDrawFrame(GL10 gl) {
...
+ float[] scratch = new float[16];
+
// Create a rotation transformation for the triangle
long time = SystemClock.uptimeMillis() % 4000L;
float angle = 0.090f * ((int) time);
Matrix.setRotateM(mRotationMatrix, 0, angle, 0, 0, -1.0f);
// Combine the rotation matrix with the projection and camera view
- Matrix.multiplyMM(mMVPMatrix, 0, mRotationMatrix, 0, mMVPMatrix, 0);
+ // Note that the mMVPMatrix factor *must be first* in order
+ // for the matrix multiplication product to be correct.
+ Matrix.multiplyMM(scratch, 0, mMVPMatrix, 0, mRotationMatrix, 0);
// Draw triangle
- mTriangle.draw(mMVPMatrix);
+ mTriangle.draw(scratch);
}
</pre>
@@ -82,8 +86,9 @@
<pre>
public MyGLSurfaceView(Context context) {
...
- // Render the view only when there is a change in the drawing data
- //setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY); // comment out for auto-rotation
+ // Render the view only when there is a change in the drawing data.
+ // To allow the triangle to rotate automatically, this line is commented out:
+ <strong>//setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);</strong>
}
</pre>
diff --git a/docs/html/training/graphics/opengl/projection.jd b/docs/html/training/graphics/opengl/projection.jd
index 2a91093..b09e74c 100644
--- a/docs/html/training/graphics/opengl/projection.jd
+++ b/docs/html/training/graphics/opengl/projection.jd
@@ -79,12 +79,12 @@
// this projection matrix is applied to object coordinates
// in the onDrawFrame() method
- Matrix.frustumM(mProjMatrix, 0, -ratio, ratio, -1, 1, 3, 7);
+ Matrix.frustumM(mProjectionMatrix, 0, -ratio, ratio, -1, 1, 3, 7);
}
</pre>
-<p>This code populates a projection matrix, {@code mProjMatrix} which you can then combine with a
-camera view transformation in the {@link android.opengl.GLSurfaceView.Renderer#onDrawFrame
+<p>This code populates a projection matrix, {@code mProjectionMatrix} which you can then combine
+with a camera view transformation in the {@link android.opengl.GLSurfaceView.Renderer#onDrawFrame
onDrawFrame()} method, which is shown in the next section.</p>
<p class="note"><strong>Note:</strong> Just applying a projection transformation to your
@@ -104,12 +104,11 @@
@Override
public void onDrawFrame(GL10 unused) {
...
-
// Set the camera position (View matrix)
- Matrix.setLookAtM(mVMatrix, 0, 0, 0, -3, 0f, 0f, 0f, 0f, 1.0f, 0.0f);
+ Matrix.setLookAtM(mViewMatrix, 0, 0, 0, -3, 0f, 0f, 0f, 0f, 1.0f, 0.0f);
// Calculate the projection and view transformation
- Matrix.multiplyMM(mMVPMatrix, 0, mProjMatrix, 0, mVMatrix, 0);
+ Matrix.multiplyMM(mMVPMatrix, 0, mProjectionMatrix, 0, mViewMatrix, 0);
// Draw shape
mTriangle.draw(mMVPMatrix);
@@ -130,7 +129,7 @@
// get handle to shape's transformation matrix
mMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
- // Apply the projection and view transformation
+ // Pass the projection and view transformation to the shader
GLES20.glUniformMatrix4fv(mMVPMatrixHandle, 1, false, mvpMatrix, 0);
// Draw the triangle
@@ -139,7 +138,7 @@
}
</pre>
-<p>Once you have correctly calulated and applied the projection and camera view transformations,
+<p>Once you have correctly calculated and applied the projection and camera view transformations,
your graphic objects are drawn in correct proportions and should look like this:</p>
diff --git a/docs/html/training/graphics/opengl/shapes.jd b/docs/html/training/graphics/opengl/shapes.jd
index 98381cc..b960bb7 100644
--- a/docs/html/training/graphics/opengl/shapes.jd
+++ b/docs/html/training/graphics/opengl/shapes.jd
@@ -50,16 +50,16 @@
OpenGL ES graphics pipeline for processing.</p>
<pre>
-class Triangle {
+public class Triangle {
private FloatBuffer vertexBuffer;
// number of coordinates per vertex in this array
static final int COORDS_PER_VERTEX = 3;
- static float triangleCoords[] = { // in counterclockwise order:
- 0.0f, 0.622008459f, 0.0f, // top
- -0.5f, -0.311004243f, 0.0f, // bottom left
- 0.5f, -0.311004243f, 0.0f // bottom right
+ static float triangleCoords[] = { // in counterclockwise order:
+ 0.0f, 0.622008459f, 0.0f, // top
+ -0.5f, -0.311004243f, 0.0f, // bottom left
+ 0.5f, -0.311004243f, 0.0f // bottom right
};
// Set color with red, green, blue and alpha (opacity) values
@@ -112,17 +112,18 @@
OpenGL ES graphics pipeline how to draw these vertices. Here’s the code for this shape:</p>
<pre>
-class Square {
+public class Square {
private FloatBuffer vertexBuffer;
private ShortBuffer drawListBuffer;
// number of coordinates per vertex in this array
static final int COORDS_PER_VERTEX = 3;
- static float squareCoords[] = { -0.5f, 0.5f, 0.0f, // top left
- -0.5f, -0.5f, 0.0f, // bottom left
- 0.5f, -0.5f, 0.0f, // bottom right
- 0.5f, 0.5f, 0.0f }; // top right
+ static float squareCoords[] = {
+ -0.5f, 0.5f, 0.0f, // top left
+ -0.5f, -0.5f, 0.0f, // bottom left
+ 0.5f, -0.5f, 0.0f, // bottom right
+ 0.5f, 0.5f, 0.0f }; // top right
private short drawOrder[] = { 0, 1, 2, 0, 2, 3 }; // order to draw vertices
diff --git a/docs/html/training/graphics/opengl/touch.jd b/docs/html/training/graphics/opengl/touch.jd
index c058a59..4c9f0c7 100644
--- a/docs/html/training/graphics/opengl/touch.jd
+++ b/docs/html/training/graphics/opengl/touch.jd
@@ -75,7 +75,9 @@
dy = dy * -1 ;
}
- mRenderer.mAngle += (dx + dy) * TOUCH_SCALE_FACTOR; // = 180.0f / 320
+ mRenderer.setAngle(
+ mRenderer.getAngle() +
+ ((dx + dy) * TOUCH_SCALE_FACTOR); // = 180.0f / 320
requestRender();
}
@@ -123,16 +125,20 @@
<pre>
public void onDrawFrame(GL10 gl) {
...
+ float[] scratch = new float[16];
+
// Create a rotation for the triangle
// long time = SystemClock.uptimeMillis() % 4000L;
// float angle = 0.090f * ((int) time);
<strong>Matrix.setRotateM(mRotationMatrix, 0, mAngle, 0, 0, -1.0f);</strong>
// Combine the rotation matrix with the projection and camera view
- Matrix.multiplyMM(mMVPMatrix, 0, mRotationMatrix, 0, mMVPMatrix, 0);
+ // Note that the mMVPMatrix factor *must be first* in order
+ // for the matrix multiplication product to be correct.
+ Matrix.multiplyMM(scratch, 0, mMVPMatrix, 0, mRotationMatrix, 0);
// Draw triangle
- mTriangle.draw(mMVPMatrix);
+ mTriangle.draw(scratch);
}
</pre>
