diff options
| -rw-r--r-- | src/jogl/classes/javax/media/opengl/awt/GLJPanel.java | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java b/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java index 40fc1001f..a5142aa98 100644 --- a/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java +++ b/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java @@ -130,19 +130,19 @@ import com.jogamp.opengl.util.texture.TextureState; using {@link GLDrawableFactory#createOffscreenDrawable(AbstractGraphicsDevice, GLCapabilitiesImmutable, GLCapabilitiesChooser, int, int) GLDrawableFactory.createOffscreenDrawable(..)}.<br/> </p> <p> - <a name="verticalFlip"> - In case</a> the drawable {@link #isGLOriented()} and {@link #setSkipGLOrientationVerticalFlip(boolean) vertical flip is not skipped}, - this component performs the required vertical flip to bring the content from OpenGL's orientation into AWT's orientation. + <a name="verticalFlip">A vertical-flip is required</a>, if the drawable {@link #isGLOriented()} and {@link #setSkipGLOrientationVerticalFlip(boolean) vertical flip is not skipped}.<br> + In this case this component performs the required vertical flip to bring the content from OpenGL's orientation into AWT's orientation.<br> + In case <a href="#fboGLSLVerticalFlip">GLSL based vertical-flip</a> is not available, + the CPU intensive {@link System#arraycopy(Object, int, Object, int, int) System.arraycopy(..)} is used line by line. See details about <a href="#fboGLSLVerticalFlip">FBO and GLSL vertical flipping</a>. </p> <p> - The OpenGL path is concluded by copying the rendered pixels an {@link BufferedImage} via {@link GL#glReadPixels(int, int, int, int, int, int, java.nio.Buffer) glReadPixels(..)} - for later Java2D composition. + For performance reasons, as well as for <a href="#bug842">GL state sideeffects</a>, + <b>{@link #setSkipGLOrientationVerticalFlip(boolean) skipping vertical flip} is highly recommended</b>! </p> <p> - In case {@link #setSkipGLOrientationVerticalFlip(boolean) vertical-flip is not skipped} and <a href="#fboGLSLVerticalFlip">GLSL based vertical-flip</a> is not performed, - {@link System#arraycopy(Object, int, Object, int, int) System.arraycopy(..)} is used line by line. - This step causes more CPU load per frame and is not hardware-accelerated. + The OpenGL path is concluded by copying the rendered pixels an {@link BufferedImage} via {@link GL#glReadPixels(int, int, int, int, int, int, java.nio.Buffer) glReadPixels(..)} + for later Java2D composition. </p> <p> Finally the Java2D compositioning takes place via via {@link Graphics#drawImage(java.awt.Image, int, int, int, int, java.awt.image.ImageObserver) Graphics.drawImage(...)} @@ -153,7 +153,8 @@ import com.jogamp.opengl.util.texture.TextureState; * </P> * <a name="fboGLSLVerticalFlip"><h5>FBO / GLSL Vertical Flip</h5></a> - In case FBO is used and GLSL is available and {@link #setSkipGLOrientationVerticalFlip(boolean) vertical flip is not skipped}, a fragment shader is utilized + If <a href="#verticalFlip">vertical flip is required</a>, + FBO is used, GLSL is available and {@link #setSkipGLOrientationVerticalFlip(boolean) vertical flip is not skipped}, a fragment shader is utilized to flip the FBO texture vertically. This hardware-accelerated step can be disabled via system property <code>jogl.gljpanel.noglsl</code>. <p> The FBO / GLSL code path uses one texture-unit and binds the FBO texture to it's active texture-target, @@ -167,7 +168,7 @@ import com.jogamp.opengl.util.texture.TextureState; The current gl-viewport is preserved. </p> <p> - <i>Warning (Bug 842)</i>: Certain GL states other than viewport and texture (see above) + <a name="bug842"><i>Warning (Bug 842)</i></a>: Certain GL states other than viewport and texture (see above) influencing rendering, will also influence the GLSL vertical flip, e.g. {@link GL#glFrontFace(int) glFrontFace}({@link GL#GL_CCW}). It is recommended to reset those states to default when leaving the {@link GLEventListener#display(GLAutoDrawable)} method! We may change this behavior in the future, i.e. preserve all influencing states. |