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authorMichael Bien <[email protected]>2010-04-12 22:27:03 +0200
committerMichael Bien <[email protected]>2010-04-12 22:27:03 +0200
commit2c85c416d85205ab98b33e1a0b0daab32d4d81ff (patch)
tree4187ba06dec81da46495a300bb4f914e931f0c58 /src/com/jogamp/opencl/demos/hellojocl/HelloJOCL.java
parentb51f2e1c254cdd74c9e43904c62694f64e6ae7e6 (diff)
changes due to package renaming in jocl.
Diffstat (limited to 'src/com/jogamp/opencl/demos/hellojocl/HelloJOCL.java')
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diff --git a/src/com/jogamp/opencl/demos/hellojocl/HelloJOCL.java b/src/com/jogamp/opencl/demos/hellojocl/HelloJOCL.java
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+package com.jogamp.opencl.demos.hellojocl;
+
+import com.jogamp.opencl.CLBuffer;
+import com.jogamp.opencl.CLCommandQueue;
+import com.jogamp.opencl.CLContext;
+import com.jogamp.opencl.CLKernel;
+import com.jogamp.opencl.CLProgram;
+import java.io.IOException;
+import java.nio.FloatBuffer;
+import java.util.Random;
+
+import static java.lang.System.*;
+import static com.jogamp.opencl.CLMemory.Mem.*;
+
+/**
+ * Hello Java OpenCL example. Adds all elements of buffer A to buffer B
+ * and stores the result in buffer C.<br/>
+ * Sample was inspired by the Nvidia VectorAdd example written in C/C++
+ * which is bundled in the Nvidia OpenCL SDK.
+ * @author Michael Bien
+ */
+public class HelloJOCL {
+
+ public static void main(String[] args) throws IOException {
+
+ int elementCount = 11444777; // Length of arrays to process
+ int localWorkSize = 256; // Local work size dimensions
+ int globalWorkSize = roundUp(localWorkSize, elementCount); // rounded up to the nearest multiple of the localWorkSize
+
+ // set up
+ CLContext context = CLContext.create();
+
+ CLProgram program = context.createProgram(HelloJOCL.class.getResourceAsStream("VectorAdd.cl")).build();
+
+ CLBuffer<FloatBuffer> clBufferA = context.createFloatBuffer(globalWorkSize, READ_ONLY);
+ CLBuffer<FloatBuffer> clBufferB = context.createFloatBuffer(globalWorkSize, READ_ONLY);
+ CLBuffer<FloatBuffer> clBufferC = context.createFloatBuffer(globalWorkSize, WRITE_ONLY);
+
+ out.println("used device memory: "
+ + (clBufferA.getSize()+clBufferB.getSize()+clBufferC.getSize())/1000000 +"MB");
+
+ // fill read buffers with random numbers (just to have test data; seed is fixed -> results will not change between runs).
+ fillBuffer(clBufferA.getBuffer(), 12345);
+ fillBuffer(clBufferB.getBuffer(), 67890);
+
+ // get a reference to the kernel functon with the name 'VectorAdd'
+ // and map the buffers to its input parameters.
+ CLKernel kernel = program.createCLKernel("VectorAdd");
+ kernel.putArgs(clBufferA, clBufferB, clBufferC).putArg(elementCount);
+
+ // create command queue on fastest device.
+ CLCommandQueue queue = context.getMaxFlopsDevice().createCommandQueue();
+
+ // asynchronous write of data to GPU device, blocking read later to get the computed results back.
+ long time = nanoTime();
+ queue.putWriteBuffer(clBufferA, false)
+ .putWriteBuffer(clBufferB, false)
+ .put1DRangeKernel(kernel, 0, globalWorkSize, localWorkSize)
+ .putReadBuffer(clBufferC, true);
+ time = nanoTime() - time;
+
+ // cleanup all resources associated with this context.
+ context.release();
+
+ // print first few elements of the resulting buffer to the console.
+ out.println("a+b=c results snapshot: ");
+ for(int i = 0; i < 10; i++)
+ out.print(clBufferC.getBuffer().get() + ", ");
+ out.println("...; " + clBufferC.getBuffer().remaining() + " more");
+
+ out.println("computation took: "+(time/1000000)+"ms");
+
+ }
+
+ private static final void fillBuffer(FloatBuffer buffer, int seed) {
+ Random rnd = new Random(seed);
+ while(buffer.remaining() != 0)
+ buffer.put(rnd.nextFloat()*100);
+ buffer.rewind();
+ }
+
+ private static final int roundUp(int groupSize, int globalSize) {
+ int r = globalSize % groupSize;
+ if (r == 0) {
+ return globalSize;
+ } else {
+ return globalSize + groupSize - r;
+ }
+ }
+
+} \ No newline at end of file