diff options
Diffstat (limited to 'src/jogl/classes/com/jogamp/opengl/math')
| -rw-r--r-- | src/jogl/classes/com/jogamp/opengl/math/geom/Frustum.java | 204 |
1 files changed, 134 insertions, 70 deletions
diff --git a/src/jogl/classes/com/jogamp/opengl/math/geom/Frustum.java b/src/jogl/classes/com/jogamp/opengl/math/geom/Frustum.java index 389c23140..b98d4ae0a 100644 --- a/src/jogl/classes/com/jogamp/opengl/math/geom/Frustum.java +++ b/src/jogl/classes/com/jogamp/opengl/math/geom/Frustum.java @@ -27,11 +27,30 @@ */ package com.jogamp.opengl.math.geom; +import com.jogamp.common.os.Platform; + /** * Derived Frustum of premultiplied projection * modelview matrix * exposing {@link #isOutside(AABBox)} test and the {@link #getPlanes() planes} itself. + * <p> + * Implementation follows the following paper:<br/> + * http://graphics.cs.ucf.edu/cap4720/fall2008/plane_extraction.pdf + * <pre> + * Fast Extraction of Viewing Frustum Planes from + * the World-View-Projection Matrix + * Authors (in alphabetical order): + * Gil Gribb <[email protected]> + * Klaus Hartmann <[email protected]> + * 06/15/2001 + * </pre> + * </p> + * <p> + * Further reference: Planes and Half-Spaces, Max Wagner <[email protected]><br/> + * http://www.emeyex.com/site/tuts/PlanesHalfSpaces.pdf + * </p> */ public class Frustum { + /** Normalized planes[l, r, b, t, n, f] */ protected Plane[] planes = new Plane[6]; /** @@ -45,15 +64,16 @@ public class Frustum { /** * Creates a defined instance w/ calculating the frustum - * using the passed float[16] as premultiplied MV*P (column major order) + * using the passed float[16] as premultiplied P*MV (column major order) */ - public Frustum(float[] mvp, int pmv_off) { + public Frustum(float[] pmv, int pmv_off) { for (int i = 0; i < 6; ++i) { planes[i] = new Plane(); } - update(mvp, pmv_off); + update(pmv, pmv_off); } + /** Plane equation := dot(n, x - p) = 0 -> ax + bc + cx + d == 0 */ public static class Plane { /** Normal of the plane */ public final float[] n = new float[3]; @@ -61,14 +81,28 @@ public class Frustum { /** Distance to origin */ public float d; - /** Return distance of plane to given point */ + /** + * Return signed distance of plane to given point. + * <ul> + * <li>If dist < 0 , then the point p lies in the negative halfspace.</li> + * <li>If dist = 0 , then the point p lies in the plane.</li> + * <li>If dist > 0 , then the point p lies in the positive halfspace.</li> + * </ul> + * A plane cuts 3D space into 2 half spaces. + * <p> + * Positive halfspace is where the plane’s normals vector points into. + * </p> + * <p> + * Negative halfspace is the <i>other side</i> of the plane, i.e. *-1 + * </p> + **/ public final float distanceTo(float x, float y, float z) { - return (n[0] * x) + (n[1] * y) + (n[2] * z) + d; + return n[0] * x + n[1] * y + n[2] * z + d; } - /** Return distance of plane to given point */ + /** Return distance of plane to given point, see {@link #distanceTo(float, float, float)}. */ public final float distanceTo(float[] p) { - return (n[0] * p[0]) + (n[1] * p[1]) + (n[2] * p[2]) + d; + return n[0] * p[0] + n[1] * p[1] + n[2] * p[2] + d; } @Override @@ -76,84 +110,116 @@ public class Frustum { return "Plane[ [ " + n[0] + ", " + n[1] + ", " + n[2] + " ], " + d + "]"; } } - + + /** Index for left plane: {@value} */ + public static final int LEFT = 0; + /** Index for right plane: {@value} */ + public static final int RIGHT = 1; + /** Index for bottom plane: {@value} */ + public static final int BOTTOM = 2; + /** Index for top plane: {@value} */ + public static final int TOP = 3; + /** Index for near plane: {@value} */ + public static final int NEAR = 4; + /** Index for far plane: {@value} */ + public static final int FAR = 5; + + /** + * Planes are ordered in the returned array as follows: + * <ul> + * <li>{@link #LEFT}</li> + * <li>{@link #RIGHT}</li> + * <li>{@link #BOTTOM}</li> + * <li>{@link #TOP}</li> + * <li>{@link #NEAR}</li> + * <li>{@link #FAR}</li> + * </ul> + * + * @return array of normalized {@link Plane}s, order see above. + */ public final Plane[] getPlanes() { return planes; } /** * Re-calculate the frustum - * using the passed float[16] as premultiplied MV*P (column major order). + * using the passed float[16] as premultiplied P*MV (column major order). */ - public void update(float[] mvp, int mvp_off) { - // Left: [30+00, 31+01, 32+02, 33+03] - // comboMatrix.m[12] + comboMatrix.m[0]; + public void update(float[] pmv, int pmv_off) { + // Left: a = m41 + m11, b = m42 + m12, c = m43 + m13, d = m44 + m14 - [1..4] row-major + // Left: a = m30 + m00, b = m31 + m01, c = m32 + m02, d = m33 + m03 - [0..3] row-major { - final Plane p = planes[0]; + final Plane p = planes[LEFT]; final float[] p_n = p.n; - p_n[0] = mvp[ mvp_off + 12 ] + mvp[ mvp_off + 0 ]; - p_n[1] = mvp[ mvp_off + 13 ] + mvp[ mvp_off + 1 ]; - p_n[2] = mvp[ mvp_off + 14 ] + mvp[ mvp_off + 2 ]; - p.d = mvp[ mvp_off + 15 ] + mvp[ mvp_off + 3 ]; + p_n[0] = pmv[ pmv_off + 3 + 0 * 4 ] + pmv[ pmv_off + 0 + 0 * 4 ]; + p_n[1] = pmv[ pmv_off + 3 + 1 * 4 ] + pmv[ pmv_off + 0 + 1 * 4 ]; + p_n[2] = pmv[ pmv_off + 3 + 2 * 4 ] + pmv[ pmv_off + 0 + 2 * 4 ]; + p.d = pmv[ pmv_off + 3 + 3 * 4 ] + pmv[ pmv_off + 0 + 3 * 4 ]; } - // Right: [30-00, 31-01, 32-02, 33-03] + // Right: a = m41 - m11, b = m42 - m12, c = m43 - m13, d = m44 - m14 - [1..4] row-major + // Right: a = m30 - m00, b = m31 - m01, c = m32 - m02, d = m33 - m03 - [0..3] row-major { - final Plane p = planes[1]; + final Plane p = planes[RIGHT]; final float[] p_n = p.n; - p_n[0] = mvp[ mvp_off + 12 ] - mvp[ mvp_off + 0 ]; - p_n[1] = mvp[ mvp_off + 13 ] - mvp[ mvp_off + 1 ]; - p_n[2] = mvp[ mvp_off + 14 ] - mvp[ mvp_off + 2 ]; - p.d = mvp[ mvp_off + 15 ] - mvp[ mvp_off + 3 ]; + p_n[0] = pmv[ pmv_off + 3 + 0 * 4 ] - pmv[ pmv_off + 0 + 0 * 4 ]; + p_n[1] = pmv[ pmv_off + 3 + 1 * 4 ] - pmv[ pmv_off + 0 + 1 * 4 ]; + p_n[2] = pmv[ pmv_off + 3 + 2 * 4 ] - pmv[ pmv_off + 0 + 2 * 4 ]; + p.d = pmv[ pmv_off + 3 + 3 * 4 ] - pmv[ pmv_off + 0 + 3 * 4 ]; } - // Bottom: [30+10, 31+11, 32+12, 33+13] + // Bottom: a = m41 + m21, b = m42 + m22, c = m43 + m23, d = m44 + m24 - [1..4] row-major + // Bottom: a = m30 + m10, b = m31 + m11, c = m32 + m12, d = m33 + m13 - [0..3] row-major { - final Plane p = planes[2]; + final Plane p = planes[BOTTOM]; final float[] p_n = p.n; - p_n[0] = mvp[ mvp_off + 12 ] + mvp[ mvp_off + 4 ]; - p_n[1] = mvp[ mvp_off + 13 ] + mvp[ mvp_off + 5 ]; - p_n[2] = mvp[ mvp_off + 14 ] + mvp[ mvp_off + 6 ]; - p.d = mvp[ mvp_off + 15 ] + mvp[ mvp_off + 7 ]; + p_n[0] = pmv[ pmv_off + 3 + 0 * 4 ] + pmv[ pmv_off + 1 + 0 * 4 ]; + p_n[1] = pmv[ pmv_off + 3 + 1 * 4 ] + pmv[ pmv_off + 1 + 1 * 4 ]; + p_n[2] = pmv[ pmv_off + 3 + 2 * 4 ] + pmv[ pmv_off + 1 + 2 * 4 ]; + p.d = pmv[ pmv_off + 3 + 3 * 4 ] + pmv[ pmv_off + 1 + 3 * 4 ]; } - // Top: [30-10, 31-11, 32-12, 33-13] + // Top: a = m41 - m21, b = m42 - m22, c = m43 - m23, d = m44 - m24 - [1..4] row-major + // Top: a = m30 - m10, b = m31 - m11, c = m32 - m12, d = m33 - m13 - [0..3] row-major { - final Plane p = planes[3]; + final Plane p = planes[TOP]; final float[] p_n = p.n; - p_n[0] = mvp[ mvp_off + 12 ] - mvp[ mvp_off + 4 ]; - p_n[1] = mvp[ mvp_off + 13 ] - mvp[ mvp_off + 5 ]; - p_n[2] = mvp[ mvp_off + 14 ] - mvp[ mvp_off + 6 ]; - p.d = mvp[ mvp_off + 15 ] - mvp[ mvp_off + 7 ]; + p_n[0] = pmv[ pmv_off + 3 + 0 * 4 ] - pmv[ pmv_off + 1 + 0 * 4 ]; + p_n[1] = pmv[ pmv_off + 3 + 1 * 4 ] - pmv[ pmv_off + 1 + 1 * 4 ]; + p_n[2] = pmv[ pmv_off + 3 + 2 * 4 ] - pmv[ pmv_off + 1 + 2 * 4 ]; + p.d = pmv[ pmv_off + 3 + 3 * 4 ] - pmv[ pmv_off + 1 + 3 * 4 ]; } - // Near: [30+20, 31+21, 32+22, 33+23] + // Near: a = m41 + m31, b = m42 + m32, c = m43 + m33, d = m44 + m34 - [1..4] row-major + // Near: a = m30 + m20, b = m31 + m21, c = m32 + m22, d = m33 + m23 - [0..3] row-major { - final Plane p = planes[4]; + final Plane p = planes[NEAR]; final float[] p_n = p.n; - p_n[0] = mvp[ mvp_off + 12 ] + mvp[ mvp_off + 8 ]; - p_n[1] = mvp[ mvp_off + 13 ] + mvp[ mvp_off + 9 ]; - p_n[2] = mvp[ mvp_off + 14 ] + mvp[ mvp_off + 10 ]; - p.d = mvp[ mvp_off + 15 ] + mvp[ mvp_off + 11 ]; + p_n[0] = pmv[ pmv_off + 3 + 0 * 4 ] + pmv[ pmv_off + 2 + 0 * 4 ]; + p_n[1] = pmv[ pmv_off + 3 + 1 * 4 ] + pmv[ pmv_off + 2 + 1 * 4 ]; + p_n[2] = pmv[ pmv_off + 3 + 2 * 4 ] + pmv[ pmv_off + 2 + 2 * 4 ]; + p.d = pmv[ pmv_off + 3 + 3 * 4 ] + pmv[ pmv_off + 2 + 3 * 4 ]; } - // Far: [30-20, 31-21, 32-22, 33-23] + // Far: a = m41 - m31, b = m42 - m32, c = m43 - m33, d = m44 - m34 - [1..4] row-major + // Far: a = m30 - m20, b = m31 - m21, c = m32 + m22, d = m33 + m23 - [0..3] row-major { - final Plane p = planes[5]; + final Plane p = planes[FAR]; final float[] p_n = p.n; - p_n[0] = mvp[ mvp_off + 12 ] - mvp[ mvp_off + 8 ]; - p_n[1] = mvp[ mvp_off + 13 ] - mvp[ mvp_off + 9 ]; - p_n[2] = mvp[ mvp_off + 14 ] - mvp[ mvp_off + 10 ]; - p.d = mvp[ mvp_off + 15 ] - mvp[ mvp_off + 11 ]; + p_n[0] = pmv[ pmv_off + 3 + 0 * 4 ] - pmv[ pmv_off + 2 + 0 * 4 ]; + p_n[1] = pmv[ pmv_off + 3 + 1 * 4 ] - pmv[ pmv_off + 2 + 1 * 4 ]; + p_n[2] = pmv[ pmv_off + 3 + 2 * 4 ] - pmv[ pmv_off + 2 + 2 * 4 ]; + p.d = pmv[ pmv_off + 3 + 3 * 4 ] - pmv[ pmv_off + 2 + 3 * 4 ]; } + // Normalize all planes for (int i = 0; i < 6; ++i) { final Plane p = planes[i]; final float[] p_n = p.n; final double invl = Math.sqrt(p_n[0] * p_n[0] + p_n[1] * p_n[1] + p_n[2] * p_n[2]); - p_n[0] *= invl; - p_n[1] *= invl; - p_n[2] *= invl; - p.d *= invl; + p_n[0] /= invl; + p_n[1] /= invl; + p_n[2] /= invl; + p.d /= invl; } } @@ -161,23 +227,16 @@ public class Frustum { final float[] low = box.getLow(); final float[] high = box.getHigh(); - if (p.distanceTo(low[0], low[1], low[2]) > 0.0f) - return true; - if (p.distanceTo(high[0], low[1], low[2]) > 0.0f) - return true; - if (p.distanceTo(low[0], high[1], low[2]) > 0.0f) + if ( p.distanceTo(low[0], low[1], low[2]) > 0.0f || + p.distanceTo(high[0], low[1], low[2]) > 0.0f || + p.distanceTo(low[0], high[1], low[2]) > 0.0f || + p.distanceTo(high[0], high[1], low[2]) > 0.0f || + p.distanceTo(low[0], low[1], high[2]) > 0.0f || + p.distanceTo(high[0], low[1], high[2]) > 0.0f || + p.distanceTo(low[0], high[1], high[2]) > 0.0f || + p.distanceTo(high[0], high[1], high[2]) > 0.0f ) { return true; - if (p.distanceTo(high[0], high[1], low[2]) > 0.0f) - return true; - if (p.distanceTo(low[0], low[1], high[2]) > 0.0f) - return true; - if (p.distanceTo(high[0], low[1], high[2]) > 0.0f) - return true; - if (p.distanceTo(low[0], high[1], high[2]) > 0.0f) - return true; - if (p.distanceTo(high[0], high[1], high[2]) > 0.0f) - return true; - + } return false; } @@ -202,9 +261,14 @@ public class Frustum { if( null == sb ) { sb = new StringBuilder(); } - sb.append("Frustum[ Planes[ ").append(planes[0]).append(", "); - sb.append(planes[1]).append(", ").append(planes[2]).append(", ").append(planes[3]).append(", ").append(planes[4]).append(", "); - sb.append(planes[5]).append(" ] ]"); + sb.append("Frustum[ Planes[ ").append(Platform.NEWLINE) + .append(" L: ").append(planes[0]).append(", ").append(Platform.NEWLINE) + .append(" R: ").append(planes[1]).append(", ").append(Platform.NEWLINE) + .append(" B: ").append(planes[2]).append(", ").append(Platform.NEWLINE) + .append(" T: ").append(planes[3]).append(", ").append(Platform.NEWLINE) + .append(" N: ").append(planes[4]).append(", ").append(Platform.NEWLINE) + .append(" F: ").append(planes[5]).append("], ").append(Platform.NEWLINE) + .append("]"); return sb; } |