tesselating path renderer unit tests

src/gpu/GrTestUtils.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrTestUtils.h"
 #include "SkMatrix.h"
 #include "SkPath.h"
 #include "SkRRect.h"
 
 #ifdef GR_TEST_UTILS
 
-namespace GrTest {
-const SkMatrix& TestMatrix(SkRandom* random) {
+static const SkMatrix& test_matrix(SkRandom* random, bool includePerspective) {
     static SkMatrix gMatrices[5];
+    static const int kPerspectiveCount = 1;
     static bool gOnce;
     if (!gOnce) {
         gOnce = true;
         gMatrices[0].reset();
         gMatrices[1].setTranslate(SkIntToScalar(-100), SkIntToScalar(100));
         gMatrices[2].setRotate(SkIntToScalar(17));
         gMatrices[3].setRotate(SkIntToScalar(185));
         gMatrices[3].postTranslate(SkIntToScalar(66), SkIntToScalar(-33));
         gMatrices[3].postScale(SkIntToScalar(2), SK_ScalarHalf);
+
+        // Perspective matrices
         gMatrices[4].setRotate(SkIntToScalar(215));
         gMatrices[4].set(SkMatrix::kMPersp0, 0.00013f);
         gMatrices[4].set(SkMatrix::kMPersp1, -0.000039f);
     }
-    return gMatrices[random->nextULessThan(static_cast<uint32_t>(SK_ARRAY_COUNT(gMatrices)))];
+
+    uint32_t count = static_cast<uint32_t>(SK_ARRAY_COUNT(gMatrices));
+    if (includePerspective) {
+        return gMatrices[random->nextULessThan(count)];
+    } else {
+        return gMatrices[random->nextULessThan(count - kPerspectiveCount)];
+    }
 }
 
+namespace GrTest {
+const SkMatrix& TestMatrix(SkRandom* random) { return test_matrix(random, true); }
+
 const SkMatrix& TestMatrixPreservesRightAngles(SkRandom* random) {
     static SkMatrix gMatrices[5];
     static bool gOnce;
     if (!gOnce) {
         gOnce = true;
         // identity
         gMatrices[0].reset();
         // translation
         gMatrices[1].setTranslate(SkIntToScalar(-100), SkIntToScalar(100));
         // scale
@@ skipping 32 matching lines @@
         // 90 degress rotation
         gMatrices[5].setRotate(90);
 
         for (size_t i = 0; i < SK_ARRAY_COUNT(gMatrices); i++) {
             SkASSERT(gMatrices[i].rectStaysRect());
         }
     }
     return gMatrices[random->nextULessThan(static_cast<uint32_t>(SK_ARRAY_COUNT(gMatrices)))];
 }
 
+const SkMatrix& TestMatrixInvertible(SkRandom* random) { return test_matrix(random, false); }
+
 const SkRect& TestRect(SkRandom* random) {
     static SkRect gRects[7];
     static bool gOnce;
     if (!gOnce) {
         gOnce = true;
         gRects[0] = SkRect::MakeWH(1.f, 1.f);
         gRects[1] = SkRect::MakeWH(1.0f, 256.0f);
         gRects[2] = SkRect::MakeWH(256.0f, 1.0f);
         gRects[4] = SkRect::MakeLargest();
         gRects[5] = SkRect::MakeLTRB(-65535.0f, -65535.0f, 65535.0f, 65535.0f);
@@ skipping 62 matching lines @@
         gPath[6].lineTo(0.0f, 10.0f);
         gPath[6].close();
     }
 
     return gPath[random->nextULessThan(static_cast<uint32_t>(SK_ARRAY_COUNT(gPath)))];
 }
 
 };
 
 #endif