diff --git a/core/test/processing/core/PMatrix2DTest.java b/core/test/processing/core/PMatrix2DTest.java
new file mode 100644
index 000000000..3f1f82f24
--- /dev/null
+++ b/core/test/processing/core/PMatrix2DTest.java
@@ -0,0 +1,186 @@
+package processing.core;
+
+import static org.junit.Assert.*;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class PMatrix2DTest {
+
+  private PMatrix2D m;
+
+  @Before
+  public void setUp() {
+    m = new PMatrix2D();
+  }
+
+  @Test
+  public void testIdentity() {
+    assertTrue("New matrix should be identity", m.isIdentity());
+    float[] arr = m.get(null);
+    assertEquals(1, arr[0], 0.0001f);  // m00
+    assertEquals(0, arr[1], 0.0001f);  // m01
+    assertEquals(0, arr[2], 0.0001f);  // m02
+    assertEquals(0, arr[3], 0.0001f);  // m10
+    assertEquals(1, arr[4], 0.0001f);  // m11
+    assertEquals(0, arr[5], 0.0001f);  // m12
+  }
+
+  @Test
+  public void testTranslate() {
+    m.translate(10, 20);
+    assertEquals(10, m.m02, 0.0001f);
+    assertEquals(20, m.m12, 0.0001f);
+  }
+
+  @Test
+  public void testRotate() {
+    m.rotate(PConstants.HALF_PI);
+    assertEquals(0, m.m00, 0.0001f);
+    assertEquals(-1, m.m01, 0.0001f); 
+    assertEquals(1, m.m10, 0.0001f); 
+    assertEquals(0, m.m11, 0.0001f);
+  }
+
+
+  @Test
+  public void testScale() {
+    m.scale(2, 3);
+    assertEquals(2, m.m00, 0.0001f);
+    assertEquals(3, m.m11, 0.0001f);
+    assertEquals(0, m.m02, 0.0001f);
+    assertEquals(0, m.m12, 0.0001f);
+  }
+
+  @Test
+  public void testShear() {
+      float shearAngle = 0.2f; 
+      m.shearX(shearAngle);
+      assertEquals(0, m.m01, 0.0001f); 
+      assertEquals((float)Math.tan(shearAngle), m.m10, 0.0001f); 
+      assertEquals(1, m.m02, 0.0001f);
+  
+      m.reset();
+      
+      m.shearY(shearAngle);
+      assertEquals(0, m.m01, 0.0001f); 
+      assertEquals(0, m.m10, 0.0001f);
+      assertEquals((float)Math.tan(shearAngle), m.m11, 0.0001f);
+      assertEquals(1, m.m02, 0.0001f); 
+  }
+
+  @Test
+  public void testApply() {
+    PMatrix2D m2 = new PMatrix2D(1, 2, 3, 4, 5, 6);
+    m.apply(m2);
+    assertEquals(m2.m00, m.m00, 0.0001f);
+    assertEquals(m2.m01, m.m01, 0.0001f);
+    assertEquals(m2.m02, m.m02, 0.0001f);
+    assertEquals(m2.m10, m.m10, 0.0001f);
+    assertEquals(m2.m11, m.m11, 0.0001f);
+    assertEquals(m2.m12, m.m12, 0.0001f);
+  }
+
+  @Test
+  public void testPreApply() {
+    PMatrix2D m1 = new PMatrix2D(1, 2, 3, 4, 5, 6);
+    m.reset(); // identity matrix
+    m.preApply(m1);
+    assertEquals(m1.m00, m.m00, 0.0001f);
+    assertEquals(m1.m01, m.m01, 0.0001f);
+    assertEquals(m1.m02, m.m02, 0.0001f);
+    assertEquals(m1.m10, m.m10, 0.0001f);
+    assertEquals(m1.m11, m.m11, 0.0001f);
+    assertEquals(m1.m12, m.m12, 0.0001f);
+  }
+
+  @Test
+  public void testMultPVector() {
+    PVector src = new PVector(1, 2, 0);
+    PVector result = m.mult(src, null);
+    assertEquals(src.x, result.x, 0.0001f);
+    assertEquals(src.y, result.y, 0.0001f);
+  }
+
+  @Test
+  public void testMultArray() {
+    float[] vec = { 1, 2 };
+    float[] out = m.mult(vec, null);
+    assertEquals(1, out[0], 0.0001f);
+    assertEquals(2, out[1], 0.0001f);
+  }
+
+  @Test
+  public void testMultXandY() {
+    float x = 10, y = 20;
+    float xOut = m.multX(x, y);
+    float yOut = m.multY(x, y);
+    assertEquals(x, xOut, 0.0001f);
+    assertEquals(y, yOut, 0.0001f);
+  }
+
+  @Test
+  public void testInvertAndDeterminant() {
+    m.set(2, 0, 5, 1, 3, 7);
+    float det = m.determinant();
+    assertEquals(6, det, 0.0001f);
+
+    boolean invertible = m.invert();
+    assertTrue("Matrix should be invertible", invertible);
+
+    PMatrix2D identity = new PMatrix2D(2, 0, 5, 1, 3, 7);
+    identity.apply(m);
+
+    assertEquals(1, identity.m00, 0.001f);
+    assertEquals(0, identity.m01, 0.001f);
+    assertEquals(0, identity.m10, 0.001f);
+    assertEquals(1, identity.m11, 0.001f);
+  }
+
+  @Test
+  public void testIdentityWarped() {
+    assertTrue(m.isIdentity());
+    assertFalse(m.isWarped());
+
+    m.translate(10, 20);
+    assertFalse(m.isIdentity());
+  }
+
+  @Test(expected = IllegalArgumentException.class)
+  public void testTranslate3DThrows() {
+    m.translate(1, 2, 3);
+  }
+
+  @Test(expected = IllegalArgumentException.class)
+  public void testRotateXThrows() {
+    m.rotateX(1);
+  }
+
+  @Test(expected = IllegalArgumentException.class)
+  public void testRotateYThrows() {
+    m.rotateY(1);
+  }
+
+  @Test(expected = IllegalArgumentException.class)
+  public void testScale3DThrows() {
+    m.scale(1, 2, 3);
+  }
+
+  @Test(expected = IllegalArgumentException.class)
+  public void testApplyPMatrix3DThrows() {
+    PMatrix3D m3d = new PMatrix3D(1, 0, 0, 0,
+                                   0, 1, 0, 0,
+                                   0, 0, 1, 0,
+                                   0, 0, 0, 1);
+    m.apply(m3d);
+  }
+
+  @Test
+  public void testGetArray() {
+    m.set(new float[]{1, 2, 0, 0, 1, 0});
+    float[] arr = m.get(null);
+    assertEquals(1, arr[0], 0.0001f);
+    assertEquals(2, arr[1], 0.0001f);
+    assertEquals(0, arr[2], 0.0001f);
+  }
+}