diff options
author | Kenneth Russel <[email protected]> | 2003-06-25 09:05:29 +0000 |
---|---|---|
committer | Kenneth Russel <[email protected]> | 2003-06-25 09:05:29 +0000 |
commit | 2179980ed660ef66a9c064d153c5de7994d431ab (patch) | |
tree | 926fa0ccc31737ad9753a64bf0451dd818652d1b /src/demos/vertexArrayRange | |
parent | 1a1ad3a33b2932187410bc8bb4bf44362a26c8b0 (diff) |
Split up net.java.games.util; moved GLUT and BufferUtils into
net.java.games.jogl.util, and moved demo-specific utility classes into
jogl-demos project under demos.util. Added nearly all JavaOne demos
into jogl-demos project; rewrote where necessary to use
ClassLoader.getResourceAsStream() instead of flat files, put into
packages and added to Makefile. Added gleem to jogl-demos project.
Added jogl.jar build rule.
git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/../svn-server-sync/jogl-demos/trunk@3 3298f667-5e0e-4b4a-8ed4-a3559d26a5f4
Diffstat (limited to 'src/demos/vertexArrayRange')
-rw-r--r-- | src/demos/vertexArrayRange/VertexArrayRange.java | 729 |
1 files changed, 729 insertions, 0 deletions
diff --git a/src/demos/vertexArrayRange/VertexArrayRange.java b/src/demos/vertexArrayRange/VertexArrayRange.java new file mode 100644 index 0000000..18bf196 --- /dev/null +++ b/src/demos/vertexArrayRange/VertexArrayRange.java @@ -0,0 +1,729 @@ +/* + * Portions Copyright (C) 2003 Sun Microsystems, Inc. + * All rights reserved. + */ + +/* + * + * COPYRIGHT NVIDIA CORPORATION 2003. ALL RIGHTS RESERVED. + * BY ACCESSING OR USING THIS SOFTWARE, YOU AGREE TO: + * + * 1) ACKNOWLEDGE NVIDIA'S EXCLUSIVE OWNERSHIP OF ALL RIGHTS + * IN AND TO THE SOFTWARE; + * + * 2) NOT MAKE OR DISTRIBUTE COPIES OF THE SOFTWARE WITHOUT + * INCLUDING THIS NOTICE AND AGREEMENT; + * + * 3) ACKNOWLEDGE THAT TO THE MAXIMUM EXTENT PERMITTED BY + * APPLICABLE LAW, THIS SOFTWARE IS PROVIDED *AS IS* AND + * THAT NVIDIA AND ITS SUPPLIERS DISCLAIM ALL WARRANTIES, + * EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED + * TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE. + * + * IN NO EVENT SHALL NVIDIA OR ITS SUPPLIERS BE LIABLE FOR ANY + * SPECIAL, INCIDENTAL, INDIRECT, OR CONSEQUENTIAL DAMAGES + * WHATSOEVER (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS + * OF BUSINESS PROFITS, BUSINESS INTERRUPTION, LOSS OF BUSINESS + * INFORMATION, OR ANY OTHER PECUNIARY LOSS), INCLUDING ATTORNEYS' + * FEES, RELATING TO THE USE OF OR INABILITY TO USE THIS SOFTWARE, + * EVEN IF NVIDIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. + * + */ + +package demos.vertexArrayRange; + +import java.awt.*; +import java.awt.event.*; +import java.nio.*; +import java.util.*; + +import net.java.games.jogl.*; + +/** <P> A port of NVidia's [tm] Vertex Array Range demonstration to + OpenGL[tm] for Java[tm] and the Java programming language. The + current web site for the demo (which does not appear to contain + the original C++ source code for this demo) is <a href = + "http://developer.nvidia.com/view.asp?IO=Using_GL_NV_fence">here</a>. </P> + + <P> This demonstration requires the following: + + <ul> + <li> A JDK 1.4 implementation + <li> an NVidia GeForce-based card + <li> a recent set of drivers + </ul> + + </P> + + <P> This demonstration illustrates the effective use of the + java.nio direct buffer classes in JDK 1.4 to access memory outside + of the Java garbage-collected heap, in particular that returned + from the NVidia-specific routine wglAllocateMemoryNV. This memory + region is used in conjunction with glVertexArrayRangeNV. </P> + + <P> On a 750 MHz PIII with an SDRAM memory bus and a GeForce 256 + running the Java HotSpot[tm] Client VM and OpenGL for Java 2.8, + this demonstration attains 90% of the speed of the compiled C++ + code, with a frame rate of 27 FPS, compared to 30 FPS for the C++ + version. On higher-end hardware (a dual 667 MHz PIII with RDRAM + and a GeForce 2) the demo currently attains between 65% and 75% of + C++ speed with the HotSpot Client and Server compilers, + respectively. </P> */ + +public class VertexArrayRange { + private boolean[] b = new boolean[256]; + private static final int SIZEOF_FLOAT = 4; + private static final int STRIP_SIZE = 48; + private int tileSize = 9 * STRIP_SIZE; + private int numBuffers = 4; + private int bufferLength = 1000000; + private int bufferSize = bufferLength * SIZEOF_FLOAT; + private static final int SIN_ARRAY_SIZE = 1024; + + private FloatBuffer bigArrayVar; + private FloatBuffer bigArraySystem; + private FloatBuffer bigArray; + private int[][] elements; + private float[] xyArray; + + static class VarBuffer { + public FloatBuffer vertices; + public FloatBuffer normals; + public int fence; + } + private VarBuffer[] buffers; + + private float[] sinArray; + private float[] cosArray; + + // Primitive: GL_QUAD_STRIP, GL_LINE_STRIP, or GL_POINTS + private int primitive = GL.GL_QUAD_STRIP; + + // Animation parameters + private float hicoef = .06f; + private float locoef = .10f; + private float hifreq = 6.1f; + private float lofreq = 2.5f; + private float phaseRate = .02f; + private float phase2Rate = -0.12f; + private float phase = 0; + private float phase2 = 0; + + // Temporaries for computation + float[] ysinlo = new float[STRIP_SIZE]; + float[] ycoslo = new float[STRIP_SIZE]; + float[] ysinhi = new float[STRIP_SIZE]; + float[] ycoshi = new float[STRIP_SIZE]; + + // For thread-safety when dealing with keypresses + private volatile boolean toggleVAR = false; + private volatile boolean toggleLighting = false; + private volatile boolean toggleLightingModel = false; + private volatile boolean recomputeElements = false; + private volatile boolean quit = false; + + // Frames-per-second computation + private boolean firstProfiledFrame; + private int profiledFrameCount; + private int numDrawElementsCalls; + private long startTimeMillis; + + private GLCanvas canvas = null; + private Animator animator; + + static class PeriodicIterator { + public PeriodicIterator(int arraySize, + float period, + float initialOffset, + float delta) { + float arrayDelta = arraySize * (delta / period); // floating-point steps-per-increment + increment = (int)(arrayDelta * (1<<16)); // fixed-point steps-per-increment + + float offset = arraySize * (initialOffset / period); // floating-point initial index + initOffset = (int)(offset * (1<<16)); // fixed-point initial index + + arraySizeMask = 0; + int i = 20; // array should be reasonably sized... + while((arraySize & (1<<i)) == 0) { + i--; + } + arraySizeMask = (1<<i)-1; + index = initOffset; + } + + public PeriodicIterator(PeriodicIterator arg) { + this.arraySizeMask = arg.arraySizeMask; + this.increment = arg.increment; + this.initOffset = arg.initOffset; + this.index = arg.index; + } + + public int getIndex() { + return (index >> 16) & arraySizeMask; + } + + public void incr() { + index += increment; + } + + public void decr() { + index -= increment; + } + + public void reset() { + index = initOffset; + } + + //---------------------------------------------------------------------- + // Internals only below this point + // + + private int arraySizeMask; + // fraction bits == 16 + private int increment; + private int initOffset; + private int index; + } + + public static void usage(String className) { + System.out.println("usage: java " + className + " [-slow]"); + System.out.println("-slow flag starts up using data in the Java heap"); + System.exit(0); + } + + public static void main(String[] args) { + new VertexArrayRange().run(args); + } + + public void run(String[] args) { + boolean startSlow = false; + + if (args.length > 1) { + usage(getClass().getName()); + } + + if (args.length == 1) { + if (args[0].equals("-slow")) { + startSlow = true; + } else { + usage(getClass().getName()); + } + } + + if (!startSlow) { + setFlag('v', true); // VAR on + } + setFlag(' ', true); // animation on + setFlag('i', true); // infinite viewer and light + + canvas = GLDrawableFactory.getFactory().createGLCanvas(new GLCapabilities()); + // canvas.setGL(new TraceGL(canvas.getGL(), System.err)); + // canvas.setGL(new DebugGL(canvas.getGL())); + VARListener listener = new VARListener(); + canvas.addGLEventListener(listener); + + animator = new Animator(canvas); + + Frame frame = new Frame("Very Simple NV_vertex_array_range demo"); + frame.setLayout(new BorderLayout()); + canvas.setSize(800, 800); + frame.add(canvas, BorderLayout.CENTER); + frame.pack(); + frame.show(); + canvas.requestFocus(); + + frame.addWindowListener(new WindowAdapter() { + public void windowClosing(WindowEvent e) { + animator.stop(); + System.exit(0); + } + }); + + animator.start(); + } + + //---------------------------------------------------------------------- + // Internals only below this point + // + + private void setFlag(char key, boolean val) { + b[((int) key) & 0xFF] = val; + } + + private boolean getFlag(char key) { + return b[((int) key) & 0xFF]; + } + + private void ensurePresent(String function) { + if (!canvas.getGL().isFunctionAvailable(function)) { + throw new RuntimeException("OpenGL routine \"" + function + "\" not available"); + } + } + + class VARListener implements GLEventListener { + boolean exiting = false; + + public void init(GLDrawable drawable) { + GL gl = drawable.getGL(); + GLU glu = drawable.getGLU(); + + // Try and disable synch-to-retrace for fastest framerate + if (gl.isFunctionAvailable("wglSwapIntervalEXT")) { + System.err.println("wglSwapIntervalEXT available; disabling sync-to-refresh for best framerate"); + gl.wglSwapIntervalEXT(0); + } + else { + System.err.println("wglSwapIntervalEXT not available; cannot disable sync-to-refresh"); + } + + try { + ensurePresent("glVertexArrayRangeNV"); + ensurePresent("glGenFencesNV"); + ensurePresent("glSetFenceNV"); + ensurePresent("glTestFenceNV"); + ensurePresent("glFinishFenceNV"); + ensurePresent("glAllocateMemoryNV"); + } catch (RuntimeException e) { + runExit(); + throw (e); + } + + gl.glEnable(GL.GL_DEPTH_TEST); + + gl.glClearColor(0, 0, 0, 0); + + gl.glEnable(GL.GL_LIGHT0); + gl.glEnable(GL.GL_LIGHTING); + gl.glEnable(GL.GL_NORMALIZE); + gl.glMaterialfv(GL.GL_FRONT_AND_BACK, GL.GL_AMBIENT, new float[] {.1f, .1f, 0, 1}); + gl.glMaterialfv(GL.GL_FRONT_AND_BACK, GL.GL_DIFFUSE, new float[] {.6f, .6f, .1f, 1}); + gl.glMaterialfv(GL.GL_FRONT_AND_BACK, GL.GL_SPECULAR, new float[] { 1, 1, .75f, 1}); + gl.glMaterialf(GL.GL_FRONT_AND_BACK, GL.GL_SHININESS, 128.f); + + gl.glLightfv(GL.GL_LIGHT0, GL.GL_POSITION, new float[] { .5f, 0, .5f, 0}); + gl.glLightModeli(GL.GL_LIGHT_MODEL_LOCAL_VIEWER, 0); + + // NOTE: it looks like GLUT (or something else) sets up the + // projection matrix in the C version of this demo. + gl.glMatrixMode(GL.GL_PROJECTION); + gl.glLoadIdentity(); + glu.gluPerspective(60, 1.0, 0.1, 100); + gl.glMatrixMode(GL.GL_MODELVIEW); + + allocateBigArray(gl, true); + allocateBuffersAndFences(gl); + + sinArray = new float[SIN_ARRAY_SIZE]; + cosArray = new float[SIN_ARRAY_SIZE]; + + for (int i = 0; i < SIN_ARRAY_SIZE; i++) { + double step = i * 2 * Math.PI / SIN_ARRAY_SIZE; + sinArray[i] = (float) Math.sin(step); + cosArray[i] = (float) Math.cos(step); + } + + if (getFlag('v')) { + gl.glEnableClientState(GL.GL_VERTEX_ARRAY_RANGE_NV); + gl.glVertexArrayRangeNV(bufferSize, bigArrayVar); + bigArray = bigArrayVar; + } else { + bigArray = bigArraySystem; + } + setupBuffers(); + gl.glEnableClientState(GL.GL_VERTEX_ARRAY); + gl.glEnableClientState(GL.GL_NORMAL_ARRAY); + + computeElements(); + + drawable.addKeyListener(new KeyAdapter() { + public void keyTyped(KeyEvent e) { + dispatchKey(e.getKeyChar()); + } + }); + } + + private void allocateBuffersAndFences(GL gl) { + buffers = new VarBuffer[numBuffers]; + int[] fences = new int[1]; + for (int i = 0; i < numBuffers; i++) { + buffers[i] = new VarBuffer(); + gl.glGenFencesNV(1, fences); + buffers[i].fence = fences[0]; + } + } + + private void setupBuffers() { + int sliceSize = bufferLength / numBuffers; + for (int i = 0; i < numBuffers; i++) { + int startIndex = i * sliceSize; + buffers[i].vertices = sliceBuffer(bigArray, startIndex, sliceSize); + buffers[i].normals = sliceBuffer(buffers[i].vertices, 3, + buffers[i].vertices.limit() - 3); + } + } + + private void dispatchKey(char k) { + setFlag(k, !getFlag(k)); + // Quit on escape or 'q' + if ((k == (char) 27) || (k == 'q')) { + runExit(); + } + + if (k == 'r') { + if (getFlag(k)) { + profiledFrameCount = 0; + numDrawElementsCalls = 0; + firstProfiledFrame = true; + } + } + + if (k == 'w') { + if (getFlag(k)) { + primitive = GL.GL_LINE_STRIP; + } else { + primitive = GL.GL_QUAD_STRIP; + } + } + + if (k == 'p') { + if (getFlag(k)) { + primitive = GL.GL_POINTS; + } else { + primitive = GL.GL_QUAD_STRIP; + } + } + + if (k == 'v') { + toggleVAR = true; + } + + if (k == 'd') { + toggleLighting = true; + } + + if (k == 'i') { + toggleLightingModel = true; + } + + if('h'==k) + hicoef += .005; + if('H'==k) + hicoef -= .005; + if('l'==k) + locoef += .005; + if('L'==k) + locoef -= .005; + if('1'==k) + lofreq += .1f; + if('2'==k) + lofreq -= .1f; + if('3'==k) + hifreq += .1f; + if('4'==k) + hifreq -= .1f; + if('5'==k) + phaseRate += .01f; + if('6'==k) + phaseRate -= .01f; + if('7'==k) + phase2Rate += .01f; + if('8'==k) + phase2Rate -= .01f; + + if('t'==k) { + if(tileSize < 864) { + tileSize += STRIP_SIZE; + recomputeElements = true; + System.err.println("tileSize = " + tileSize); + } + } + + if('T'==k) { + if(tileSize > STRIP_SIZE) { + tileSize -= STRIP_SIZE; + recomputeElements = true; + System.err.println("tileSize = " + tileSize); + } + } + } + + public void display(GLDrawable drawable) { + // Don't try to do OpenGL operations if we're tearing things down + if (quit) { + return; + } + + GL gl = drawable.getGL(); + GLU glu = drawable.getGLU(); + + // Check to see whether to animate + if (getFlag(' ')) { + phase += phaseRate; + phase2 += phase2Rate; + + if (phase > (float) (20 * Math.PI)) { + phase = 0; + } + + if (phase2 < (float) (-20 * Math.PI)) { + phase2 = 0; + } + } + + PeriodicIterator loX = + new PeriodicIterator(SIN_ARRAY_SIZE, (float) (2 * Math.PI), phase, (float) ((1.f/tileSize)*lofreq*Math.PI)); + PeriodicIterator loY = new PeriodicIterator(loX); + PeriodicIterator hiX = + new PeriodicIterator(SIN_ARRAY_SIZE, (float) (2 * Math.PI), phase2, (float) ((1.f/tileSize)*hifreq*Math.PI)); + PeriodicIterator hiY = new PeriodicIterator(hiX); + + if (toggleVAR) { + if (getFlag('v')) { + gl.glEnableClientState(GL.GL_VERTEX_ARRAY_RANGE_NV); + gl.glVertexArrayRangeNV(bufferSize, bigArrayVar); + bigArray = bigArrayVar; + } else { + gl.glDisableClientState(GL.GL_VERTEX_ARRAY_RANGE_NV); + bigArray = bigArraySystem; + } + toggleVAR = false; + setupBuffers(); + } + + if (toggleLighting) { + if (getFlag('d')) { + gl.glDisable(GL.GL_LIGHTING); + } else { + gl.glEnable(GL.GL_LIGHTING); + } + toggleLighting = false; + } + + if (toggleLightingModel) { + if(getFlag('i')) { + // infinite light + gl.glLightfv(GL.GL_LIGHT0, GL.GL_POSITION, new float[] { .5f, 0, .5f, 0 }); + gl.glLightModeli(GL.GL_LIGHT_MODEL_LOCAL_VIEWER, 0); + } else { + gl.glLightfv(GL.GL_LIGHT0, GL.GL_POSITION, new float[] { .5f, 0, -.5f,1 }); + gl.glLightModeli(GL.GL_LIGHT_MODEL_LOCAL_VIEWER, 1); + } + toggleLightingModel = false; + } + + if (recomputeElements) { + computeElements(); + recomputeElements = false; + } + + gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT); + + gl.glPushMatrix(); + + final float[] modelViewMatrix = new float[] { + 1, 0, 0, 0, + 0, 1, 0, 0, + 0, 0, 1, 0, + 0, 0, -1, 1 + }; + gl.glLoadMatrixf(modelViewMatrix); + + // FIXME: add mouse interaction + // camera.apply_inverse_transform(); + // object.apply_transform(); + + int cur = 0; + int numSlabs = tileSize / STRIP_SIZE; + + for(int slab = numSlabs; --slab>=0; ) { + cur = slab % numBuffers; + if (slab >= numBuffers) { + if (!gl.glTestFenceNV(buffers[cur].fence)) { + gl.glFinishFenceNV(buffers[cur].fence); + } + } + + FloatBuffer v = buffers[cur].vertices; + int vertexIndex = 0; + + gl.glVertexPointer(3, GL.GL_FLOAT, 6 * SIZEOF_FLOAT, v); + gl.glNormalPointer(GL.GL_FLOAT, 6 * SIZEOF_FLOAT, buffers[cur].normals); + + for(int jj=STRIP_SIZE; --jj>=0; ) { + ysinlo[jj] = sinArray[loY.getIndex()]; + ycoslo[jj] = cosArray[loY.getIndex()]; loY.incr(); + ysinhi[jj] = sinArray[hiY.getIndex()]; + ycoshi[jj] = cosArray[hiY.getIndex()]; hiY.incr(); + } + loY.decr(); + hiY.decr(); + + for(int i = tileSize; --i>=0; ) { + float x = xyArray[i]; + int loXIndex = loX.getIndex(); + int hiXIndex = hiX.getIndex(); + + int jOffset = (STRIP_SIZE-1)*slab; + float nx = locoef * -cosArray[loXIndex] + hicoef * -cosArray[hiXIndex]; + + // Help the HotSpot Client Compiler by hoisting loop + // invariant variables into locals. Note that this may be + // good practice for innermost loops anyway since under + // the new memory model operations like accidental + // synchronization may force any compiler to reload these + // fields from memory, destroying their ability to + // optimize. + float locoef_tmp = locoef; + float hicoef_tmp = hicoef; + float[] ysinlo_tmp = ysinlo; + float[] ysinhi_tmp = ysinhi; + float[] ycoslo_tmp = ycoslo; + float[] ycoshi_tmp = ycoshi; + float[] sinArray_tmp = sinArray; + float[] xyArray_tmp = xyArray; + + for(int j = STRIP_SIZE; --j>=0; ) { + float y; + + y = xyArray_tmp[j + jOffset]; + + float ny; + + v.put(vertexIndex, x); + v.put(vertexIndex + 1, y); + v.put(vertexIndex + 2, (locoef_tmp * (sinArray_tmp[loXIndex] + ysinlo_tmp[j]) + + hicoef_tmp * (sinArray_tmp[hiXIndex] + ysinhi_tmp[j]))); + v.put(vertexIndex + 3, nx); + ny = locoef_tmp * -ycoslo_tmp[j] + hicoef_tmp * -ycoshi_tmp[j]; + v.put(vertexIndex + 4, ny); + v.put(vertexIndex + 5, .15f); //.15f * (1.f - sqrt(nx * nx + ny * ny)); + vertexIndex += 6; + } + loX.incr(); + hiX.incr(); + } + loX.reset(); + hiX.reset(); + + for (int i = 0; i < elements.length; i++) { + ++numDrawElementsCalls; + gl.glDrawElements(primitive, elements[i].length, GL.GL_UNSIGNED_INT, elements[i]); + if(getFlag('f')) { + gl.glFlush(); + } + } + + gl.glSetFenceNV(buffers[cur].fence, GL.GL_ALL_COMPLETED_NV); + } + + gl.glPopMatrix(); + + gl.glFinishFenceNV(buffers[cur].fence); + + if (getFlag('r')) { + if (!firstProfiledFrame) { + if (++profiledFrameCount == 30) { + long endTimeMillis = System.currentTimeMillis(); + double secs = (endTimeMillis - startTimeMillis) / 1000.0; + double fps = 30.0 / secs; + double ppf = tileSize * tileSize * 2; + double mpps = ppf * fps / 1000000.0; + System.err.println("fps: " + fps + " polys/frame: " + ppf + " million polys/sec: " + mpps + + " DrawElements calls/frame: " + (numDrawElementsCalls / 30)); + profiledFrameCount = 0; + numDrawElementsCalls = 0; + startTimeMillis = System.currentTimeMillis(); + } + } else { + startTimeMillis = System.currentTimeMillis(); + firstProfiledFrame = false; + + } + } + } + + public void reshape(GLDrawable drawable, int x, int y, int width, int height) {} + + // Unused routines + public void displayChanged(GLDrawable drawable, boolean modeChanged, boolean deviceChanged) {} + + private void runExit() { + quit = true; + // Note: calling System.exit() synchronously inside the draw, + // reshape or init callbacks can lead to deadlocks on certain + // platforms (in particular, X11) because the JAWT's locking + // routines cause a global AWT lock to be grabbed. Run the + // exit routine in another thread and cause this one to + // terminate by throwing an exception out of it. + new Thread(new Runnable() { + public void run() { + animator.stop(); + System.exit(0); + } + }).start(); + } + } // end class VARListener + + private void allocateBigArray(GL gl, boolean tryAgain) { + float priority = .5f; + + bigArraySystem = setupBuffer(ByteBuffer.allocateDirect(bufferSize)); + + float megabytes = (bufferSize / 1000000.f); + try { + bigArrayVar = setupBuffer(gl.glAllocateMemoryNV(bufferSize, 0, 0, priority)); + } + catch (OutOfMemoryError e1) { + // Try a higher priority + try { + bigArrayVar = setupBuffer(gl.glAllocateMemoryNV(bufferSize, 0, 0, 1.f)); + } + catch (OutOfMemoryError e2) { + if (!tryAgain) { + throw new RuntimeException("Unable to allocate " + megabytes + + " megabytes of fast memory. Giving up."); + } + + System.err.println("Unable to allocate " + megabytes + + " megabytes of fast memory. Trying less."); + bufferSize /= 2; + numBuffers /= 2; + allocateBigArray(gl, false); + return; + } + } + + System.err.println("Allocated " + megabytes + " megabytes of fast memory"); + } + + private FloatBuffer setupBuffer(ByteBuffer buf) { + buf.order(ByteOrder.nativeOrder()); + return buf.asFloatBuffer(); + } + + private FloatBuffer sliceBuffer(FloatBuffer array, + int sliceStartIndex, int sliceLength) { + array.position(sliceStartIndex); + FloatBuffer ret = array.slice(); + array.position(0); + ret.limit(sliceLength); + return ret; + } + + private void computeElements() { + xyArray = new float[tileSize]; + for (int i = 0; i < tileSize; i++) { + xyArray[i] = i / (tileSize - 1.0f) - 0.5f; + } + + elements = new int[tileSize - 1][]; + for (int i = 0; i < tileSize - 1; i++) { + elements[i] = new int[2 * STRIP_SIZE]; + for (int j = 0; j < 2 * STRIP_SIZE; j += 2) { + elements[i][j] = i * STRIP_SIZE + (j / 2); + elements[i][j+1] = (i + 1) * STRIP_SIZE + (j / 2); + } + } + } +} |