opengl/java/android/opengl/GLU.java - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2007 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package android.opengl;

 import javax.microedition.khronos.opengles.GL10;

 /**
  * A set of GL utilities inspired by the OpenGL Utility Toolkit.
  *
  */

 public class GLU {

     /**
      * Return an error string from a GL or GLU error code.
      *
      * @param error - a GL or GLU error code.
      * @return the error string for the input error code, or NULL if the input
      *         was not a valid GL or GLU error code.
      */
     public static String gluErrorString(int error) {
         switch (error) {
         case GL10.GL_NO_ERROR:
             return "no error";
         case GL10.GL_INVALID_ENUM:
             return "invalid enum";
         case GL10.GL_INVALID_VALUE:
             return "invalid value";
         case GL10.GL_INVALID_OPERATION:
             return "invalid operation";
         case GL10.GL_STACK_OVERFLOW:
             return "stack overflow";
         case GL10.GL_STACK_UNDERFLOW:
             return "stack underflow";
         case GL10.GL_OUT_OF_MEMORY:
             return "out of memory";
         default:
             return null;
         }
     }

     /**
      * Define a viewing transformation in terms of an eye point, a center of
      * view, and an up vector.
      *
      * @param gl a GL10 interface
      * @param eyeX eye point X
      * @param eyeY eye point Y
      * @param eyeZ eye point Z
      * @param centerX center of view X
      * @param centerY center of view Y
      * @param centerZ center of view Z
      * @param upX up vector X
      * @param upY up vector Y
      * @param upZ up vector Z
      */
     public static void gluLookAt(GL10 gl, float eyeX, float eyeY, float eyeZ,
             float centerX, float centerY, float centerZ, float upX, float upY,
             float upZ) {

         float[] scratch = sScratch;
         synchronized(scratch) {
             Matrix.setLookAtM(scratch, 0, eyeX, eyeY, eyeZ, centerX, centerY, centerZ,
                     upX, upY, upZ);
             gl.glMultMatrixf(scratch, 0);
         }
     }

     /**
      * Set up a 2D orthographic projection matrix
      *
      * @param gl
      * @param left
      * @param right
      * @param bottom
      * @param top
      */
     public static void gluOrtho2D(GL10 gl, float left, float right,
             float bottom, float top) {
         gl.glOrthof(left, right, bottom, top, -1.0f, 1.0f);
     }

     /**
      * Set up a perspective projection matrix
      *
      * @param gl a GL10 interface
      * @param fovy specifies the field of view angle, in degrees, in the Y
      *        direction.
      * @param aspect specifies the aspect ration that determins the field of
      *        view in the x direction. The aspect ratio is the ratio of x
      *        (width) to y (height).
      * @param zNear specifies the distance from the viewer to the near clipping
      *        plane (always positive).
      * @param zFar specifies the distance from the viewer to the far clipping
      *        plane (always positive).
      */
     public static void gluPerspective(GL10 gl, float fovy, float aspect,
             float zNear, float zFar) {
         float top = zNear * (float) Math.tan(fovy * (Math.PI / 360.0));
         float bottom = -top;
         float left = bottom * aspect;
         float right = top * aspect;
         gl.glFrustumf(left, right, bottom, top, zNear, zFar);
     }

     /**
      * Map object coordinates into window coordinates. gluProject transforms the
      * specified object coordinates into window coordinates using model, proj,
      * and view. The result is stored in win.
      * <p>
      * Note that you can use the OES_matrix_get extension, if present, to get
      * the current modelView and projection matrices.
      *
      * @param objX object coordinates X
      * @param objY object coordinates Y
      * @param objZ object coordinates Z
      * @param model the current modelview matrix
      * @param modelOffset the offset into the model array where the modelview
      *        maxtrix data starts.
      * @param project the current projection matrix
      * @param projectOffset the offset into the project array where the project
      *        matrix data starts.
      * @param view the current view, {x, y, width, height}
      * @param viewOffset the offset into the view array where the view vector
      *        data starts.
      * @param win the output vector {winX, winY, winZ}, that returns the
      *        computed window coordinates.
      * @param winOffset the offset into the win array where the win vector data
      *        starts.
      * @return A return value of GL_TRUE indicates success, a return value of
      *         GL_FALSE indicates failure.
      */
     public static int gluProject(float objX, float objY, float objZ,
             float[] model, int modelOffset, float[] project, int projectOffset,
             int[] view, int viewOffset, float[] win, int winOffset) {
         float[] scratch = sScratch;
         synchronized(scratch) {
             final int M_OFFSET = 0; // 0..15
             final int V_OFFSET = 16; // 16..19
             final int V2_OFFSET = 20; // 20..23
             Matrix.multiplyMM(scratch, M_OFFSET, project, projectOffset,
                     model, modelOffset);

             scratch[V_OFFSET + 0] = objX;
             scratch[V_OFFSET + 1] = objY;
             scratch[V_OFFSET + 2] = objZ;
             scratch[V_OFFSET + 3] = 1.0f;

             Matrix.multiplyMV(scratch, V2_OFFSET,
                     scratch, M_OFFSET, scratch, V_OFFSET);

             float w = scratch[V2_OFFSET + 3];
             if (w == 0.0f) {
                 return GL10.GL_FALSE;
             }

             float rw = 1.0f / w;

             win[winOffset] =
                     view[viewOffset] + view[viewOffset + 2]
                             * (scratch[V2_OFFSET + 0] * rw + 1.0f)
                             * 0.5f;
             win[winOffset + 1] =
                     view[viewOffset + 1] + view[viewOffset + 3]
                             * (scratch[V2_OFFSET + 1] * rw + 1.0f) * 0.5f;
             win[winOffset + 2] = (scratch[V2_OFFSET + 2] * rw + 1.0f) * 0.5f;
         }

         return GL10.GL_TRUE;
     }

     /**
      * Map window coordinates to object coordinates. gluUnProject maps the
      * specified window coordinates into object coordinates using model, proj,
      * and view. The result is stored in obj.
      * <p>
      * Note that you can use the OES_matrix_get extension, if present, to get
      * the current modelView and projection matrices.
      *
      * @param winX window coordinates X
      * @param winY window coordinates Y
      * @param winZ window coordinates Z
      * @param model the current modelview matrix
      * @param modelOffset the offset into the model array where the modelview
      *        maxtrix data starts.
      * @param project the current projection matrix
      * @param projectOffset the offset into the project array where the project
      *        matrix data starts.
      * @param view the current view, {x, y, width, height}
      * @param viewOffset the offset into the view array where the view vector
      *        data starts.
      * @param obj the output vector {objX, objY, objZ}, that returns the
      *        computed object coordinates.
      * @param objOffset the offset into the obj array where the obj vector data
      *        starts.
      * @return A return value of GL10.GL_TRUE indicates success, a return value
      *         of GL10.GL_FALSE indicates failure.
      */
     public static int gluUnProject(float winX, float winY, float winZ,
             float[] model, int modelOffset, float[] project, int projectOffset,
             int[] view, int viewOffset, float[] obj, int objOffset) {
         float[] scratch = sScratch;
         synchronized(scratch) {
             final int PM_OFFSET = 0; // 0..15
             final int INVPM_OFFSET = 16; // 16..31
                final int V_OFFSET = 0; // 0..3 Reuses PM_OFFSET space
             Matrix.multiplyMM(scratch, PM_OFFSET, project, projectOffset,
                     model, modelOffset);

             if (!Matrix.invertM(scratch, INVPM_OFFSET, scratch, PM_OFFSET)) {
                 return GL10.GL_FALSE;
             }

             scratch[V_OFFSET + 0] =
                     2.0f * (winX - view[viewOffset + 0]) / view[viewOffset + 2]
                             - 1.0f;
             scratch[V_OFFSET + 1] =
                     2.0f * (winY - view[viewOffset + 1]) / view[viewOffset + 3]
                             - 1.0f;
             scratch[V_OFFSET + 2] = 2.0f * winZ - 1.0f;
             scratch[V_OFFSET + 3] = 1.0f;

             Matrix.multiplyMV(obj, objOffset, scratch, INVPM_OFFSET,
                     scratch, V_OFFSET);
         }

         return GL10.GL_TRUE;
     }

     private static final float[] sScratch = new float[32];
  }
	/*
	* Copyright (C) 2007 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package android.opengl;

	import javax.microedition.khronos.opengles.GL10;

	/**
	* A set of GL utilities inspired by the OpenGL Utility Toolkit.
	*
	*/

	public class GLU {

	/**
	* Return an error string from a GL or GLU error code.
	*
	* @param error - a GL or GLU error code.
	* @return the error string for the input error code, or NULL if the input
	* was not a valid GL or GLU error code.
	*/
	public static String gluErrorString(int error) {
	switch (error) {
	case GL10.GL_NO_ERROR:
	return "no error";
	case GL10.GL_INVALID_ENUM:
	return "invalid enum";
	case GL10.GL_INVALID_VALUE:
	return "invalid value";
	case GL10.GL_INVALID_OPERATION:
	return "invalid operation";
	case GL10.GL_STACK_OVERFLOW:
	return "stack overflow";
	case GL10.GL_STACK_UNDERFLOW:
	return "stack underflow";
	case GL10.GL_OUT_OF_MEMORY:
	return "out of memory";
	default:
	return null;
	}
	}

	/**
	* Define a viewing transformation in terms of an eye point, a center of
	* view, and an up vector.
	*
	* @param gl a GL10 interface
	* @param eyeX eye point X
	* @param eyeY eye point Y
	* @param eyeZ eye point Z
	* @param centerX center of view X
	* @param centerY center of view Y
	* @param centerZ center of view Z
	* @param upX up vector X
	* @param upY up vector Y
	* @param upZ up vector Z
	*/
	public static void gluLookAt(GL10 gl, float eyeX, float eyeY, float eyeZ,
	float centerX, float centerY, float centerZ, float upX, float upY,
	float upZ) {

	float[] scratch = sScratch;
	synchronized(scratch) {
	Matrix.setLookAtM(scratch, 0, eyeX, eyeY, eyeZ, centerX, centerY, centerZ,
	upX, upY, upZ);
	gl.glMultMatrixf(scratch, 0);
	}
	}

	/**
	* Set up a 2D orthographic projection matrix
	*
	* @param gl
	* @param left
	* @param right
	* @param bottom
	* @param top
	*/
	public static void gluOrtho2D(GL10 gl, float left, float right,
	float bottom, float top) {
	gl.glOrthof(left, right, bottom, top, -1.0f, 1.0f);
	}

	/**
	* Set up a perspective projection matrix
	*
	* @param gl a GL10 interface
	* @param fovy specifies the field of view angle, in degrees, in the Y
	* direction.
	* @param aspect specifies the aspect ration that determins the field of
	* view in the x direction. The aspect ratio is the ratio of x
	* (width) to y (height).
	* @param zNear specifies the distance from the viewer to the near clipping
	* plane (always positive).
	* @param zFar specifies the distance from the viewer to the far clipping
	* plane (always positive).
	*/
	public static void gluPerspective(GL10 gl, float fovy, float aspect,
	float zNear, float zFar) {
	float top = zNear * (float) Math.tan(fovy * (Math.PI / 360.0));
	float bottom = -top;
	float left = bottom * aspect;
	float right = top * aspect;
	gl.glFrustumf(left, right, bottom, top, zNear, zFar);
	}

	/**
	* Map object coordinates into window coordinates. gluProject transforms the
	* specified object coordinates into window coordinates using model, proj,
	* and view. The result is stored in win.
	* <p>
	* Note that you can use the OES_matrix_get extension, if present, to get
	* the current modelView and projection matrices.
	*
	* @param objX object coordinates X
	* @param objY object coordinates Y
	* @param objZ object coordinates Z
	* @param model the current modelview matrix
	* @param modelOffset the offset into the model array where the modelview
	* maxtrix data starts.
	* @param project the current projection matrix
	* @param projectOffset the offset into the project array where the project
	* matrix data starts.
	* @param view the current view, {x, y, width, height}
	* @param viewOffset the offset into the view array where the view vector
	* data starts.
	* @param win the output vector {winX, winY, winZ}, that returns the
	* computed window coordinates.
	* @param winOffset the offset into the win array where the win vector data
	* starts.
	* @return A return value of GL_TRUE indicates success, a return value of
	* GL_FALSE indicates failure.
	*/
	public static int gluProject(float objX, float objY, float objZ,
	float[] model, int modelOffset, float[] project, int projectOffset,
	int[] view, int viewOffset, float[] win, int winOffset) {
	float[] scratch = sScratch;
	synchronized(scratch) {
	final int M_OFFSET = 0; // 0..15
	final int V_OFFSET = 16; // 16..19
	final int V2_OFFSET = 20; // 20..23
	Matrix.multiplyMM(scratch, M_OFFSET, project, projectOffset,
	model, modelOffset);

	scratch[V_OFFSET + 0] = objX;
	scratch[V_OFFSET + 1] = objY;
	scratch[V_OFFSET + 2] = objZ;
	scratch[V_OFFSET + 3] = 1.0f;

	Matrix.multiplyMV(scratch, V2_OFFSET,
	scratch, M_OFFSET, scratch, V_OFFSET);

	float w = scratch[V2_OFFSET + 3];
	if (w == 0.0f) {
	return GL10.GL_FALSE;
	}

	float rw = 1.0f / w;

	win[winOffset] =
	view[viewOffset] + view[viewOffset + 2]
	* (scratch[V2_OFFSET + 0] * rw + 1.0f)
	* 0.5f;
	win[winOffset + 1] =
	view[viewOffset + 1] + view[viewOffset + 3]
	* (scratch[V2_OFFSET + 1] * rw + 1.0f) * 0.5f;
	win[winOffset + 2] = (scratch[V2_OFFSET + 2] * rw + 1.0f) * 0.5f;
	}

	return GL10.GL_TRUE;
	}

	/**
	* Map window coordinates to object coordinates. gluUnProject maps the
	* specified window coordinates into object coordinates using model, proj,
	* and view. The result is stored in obj.
	* <p>
	* Note that you can use the OES_matrix_get extension, if present, to get
	* the current modelView and projection matrices.
	*
	* @param winX window coordinates X
	* @param winY window coordinates Y
	* @param winZ window coordinates Z
	* @param model the current modelview matrix
	* @param modelOffset the offset into the model array where the modelview
	* maxtrix data starts.
	* @param project the current projection matrix
	* @param projectOffset the offset into the project array where the project
	* matrix data starts.
	* @param view the current view, {x, y, width, height}
	* @param viewOffset the offset into the view array where the view vector
	* data starts.
	* @param obj the output vector {objX, objY, objZ}, that returns the
	* computed object coordinates.
	* @param objOffset the offset into the obj array where the obj vector data
	* starts.
	* @return A return value of GL10.GL_TRUE indicates success, a return value
	* of GL10.GL_FALSE indicates failure.
	*/
	public static int gluUnProject(float winX, float winY, float winZ,
	float[] model, int modelOffset, float[] project, int projectOffset,
	int[] view, int viewOffset, float[] obj, int objOffset) {
	float[] scratch = sScratch;
	synchronized(scratch) {
	final int PM_OFFSET = 0; // 0..15
	final int INVPM_OFFSET = 16; // 16..31
	final int V_OFFSET = 0; // 0..3 Reuses PM_OFFSET space
	Matrix.multiplyMM(scratch, PM_OFFSET, project, projectOffset,
	model, modelOffset);

	if (!Matrix.invertM(scratch, INVPM_OFFSET, scratch, PM_OFFSET)) {
	return GL10.GL_FALSE;
	}

	scratch[V_OFFSET + 0] =
	2.0f * (winX - view[viewOffset + 0]) / view[viewOffset + 2]
	- 1.0f;
	scratch[V_OFFSET + 1] =
	2.0f * (winY - view[viewOffset + 1]) / view[viewOffset + 3]
	- 1.0f;
	scratch[V_OFFSET + 2] = 2.0f * winZ - 1.0f;
	scratch[V_OFFSET + 3] = 1.0f;

	Matrix.multiplyMV(obj, objOffset, scratch, INVPM_OFFSET,
	scratch, V_OFFSET);
	}

	return GL10.GL_TRUE;
	}

	private static final float[] sScratch = new float[32];
	}