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GluUnProject Android OpenGL ES 1.1 Usage

I am trying to use gluUnProject to convert window coords to world coords. I am not trying to get a working sample in an emulator or older Android systems (with OpenGL ES v1.0), and this is not a question of the availability of GL functions. I am trying to work with a real device using OpenGL ES 1.1, and glGet functions return non-zero results.

There is a sample:

public Vector3 translateScreenCoordsToWorld(Vector2 screenCoords) {
gl.glLoadIdentity();

final Matrix4x4 modelViewMatrix = new Matrix4x4();
final Matrix4x4 projectMatrix = new Matrix4x4();

int[] viewVectorParams = new int[4];
gl.glGetIntegerv(GL11.GL_VIEWPORT,viewVectorParams,0);
gl.glGetFloatv(GL11.GL_MODELVIEW_MATRIX,modelViewMatrix.buffer,0);
gl.glGetFloatv(GL11.GL_PROJECTION_MATRIX,projectMatrix.buffer,0);

float[] output = new float[4];
GLU.gluUnProject(
    screenCoords.x, screenCoords.y, 0, 
    modelViewMatrix.buffer, 0, 
    projectMatrix.buffer, 0, 
    viewVectorParams, 0, 
    output, 0);             

return new Vector3(output[0],output[1],output[2]);

}

Matrix4x4 is just a wrapper for the float [] buffer;

Using this function, I try to create a plane to fill the entire screen or determine the maximum world coordinates for the current forecast matrix, but it does not work at all, because I'm not sure that I use these functions correctly.

, translateScreenCoordsToWorld ( Vector2 (480,800)), Vector3 (0.27f, 0.42f, -1.0f).

- gluUnProject GL_PROJECTION .

. :( :

public Vector3 translateScreenCoordsToWorld(Vector2 screenCoords) {

float winX = screenCoords.x, winY = screenCoords.y, winZ = 0;
winY = (float)currentViewVectorParams[3] - winY;

float[] output = new float[4];
GLU.gluUnProject(
    winX, winY, winZ, 
    currentModelViewMatrix.buffer, 0, 
    currentProjectMatrix.buffer, 0, 
    currentViewVectorParams, 0, 
    output, 0
);              

Vector3 nearPlane = new Vector3(output[0],output[1],output[2]);
winZ = 1.0f;        
GLU.gluUnProject(
    winX, winY, winZ, 
    currentModelViewMatrix.buffer, 0, 
    currentProjectMatrix.buffer, 0, 
    currentViewVectorParams, 0, 
    output, 0
);              
Vector3 farPlane = new Vector3(output[0],output[1],output[2]);

farPlane.sub(nearPlane);
farPlane.div( nearPlane.length());

float dot1, dot2;

Vector3 pointInPlane = new Vector3(), pointPlaneNormal = new Vector3(0,0,-1);
pointInPlane.sub( nearPlane );

dot1 = (pointPlaneNormal.x * pointInPlane.x) + (pointPlaneNormal.y * pointInPlane.y) + (pointPlaneNormal.z * pointInPlane.z);
dot2 = (pointPlaneNormal.x * farPlane.x) + (pointPlaneNormal.y * farPlane.y ) +(pointPlaneNormal.z * farPlane.z);

float t = dot1/dot2;
farPlane.mul(t);

return farPlane.add(nearPlane);
}

:

public void updateCamera() {
Camera camera = scene.getCamera();
GLU.gluLookAt(gl, 
    camera.position.x, camera.position.y, camera.position.z,
    camera.target.x, camera.target.y, camera.target.z,
    camera.upAxis.x, camera.upAxis.y, camera.upAxis.z
);

    gl.glGetIntegerv(GL11.GL_VIEWPORT,currentViewVectorParams,0);       
    gl.glGetFloatv(GL11.GL_MODELVIEW_MATRIX, currentModelViewMatrix.buffer,0);
    gl.glGetFloatv(GL11.GL_PROJECTION_MATRIX,currentProjectMatrix.buffer,0);
}

:

camera.position = { 0, 0, 65 };     
camera.target = { 0, 0, 0 }
camera.upAxis = { 0, 1, 0 }
+5
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