jogamp › jogl

Why does the RGB value always equal to (0, 0, 0) when I use gl2.glReadPixels(e.x, viewport[3] - e.y, 1, 1, GL2.GL_RGB, GL2.GL_FLOAT, FloatBuffer.wrap(color));

Classic

List

Threaded

2 messages Options

Irene Tang

Why does the RGB value always equal to (0, 0, 0) when I use gl2.glReadPixels(e.x, viewport[3] - e.y, 1, 1, GL2.GL_RGB, GL2.GL_FLOAT, FloatBuffer.wrap(color));

SceneObject.java
BasicObject.java
Draw.java

elect

Re: Why does the RGB value always equal to (0, 0, 0) when I use gl2.glReadPixels(e.x, viewport[3] - e.y, 1, 1, GL2.GL_RGB, GL2.GL_FLOAT, FloatBuffer.wrap(color));

Because it means at that moment when you read that pixel that is its value.

You should read this to understand problems of deprecated (fixed function) opengl and benefits of the current one