Adding isOpaque method to skia shader classes
REVIEW=http://codereview.appspot.com/5451102/
TEST=unit test ShaderOpacity
git-svn-id: http://skia.googlecode.com/svn/trunk@2840 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tests/ShaderOpacityTest.cpp b/tests/ShaderOpacityTest.cpp
new file mode 100644
index 0000000..a8177ee
--- /dev/null
+++ b/tests/ShaderOpacityTest.cpp
@@ -0,0 +1,119 @@
+
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#include "Test.h"
+#include "SkShader.h"
+#include "SkGradientShader.h"
+#include "SkColorShader.h"
+
+static void test_bitmap(skiatest::Reporter* reporter) {
+ SkBitmap bmp;
+ bmp.setConfig(SkBitmap::kARGB_8888_Config, 2, 2);
+
+ // test 1: bitmap without pixel data
+ SkShader* shader = SkShader::CreateBitmapShader(bmp,
+ SkShader::kClamp_TileMode, SkShader::kClamp_TileMode);
+ REPORTER_ASSERT(reporter, shader);
+ REPORTER_ASSERT(reporter, !shader->isOpaque());
+ shader->unref();
+
+ // From this point on, we have pixels
+ bmp.allocPixels();
+
+ // test 2: not opaque by default
+ shader = SkShader::CreateBitmapShader(bmp,
+ SkShader::kClamp_TileMode, SkShader::kClamp_TileMode);
+ REPORTER_ASSERT(reporter, shader);
+ REPORTER_ASSERT(reporter, !shader->isOpaque());
+ shader->unref();
+
+ // test 3: explicitly opaque
+ bmp.setIsOpaque(true);
+ shader = SkShader::CreateBitmapShader(bmp,
+ SkShader::kClamp_TileMode, SkShader::kClamp_TileMode);
+ REPORTER_ASSERT(reporter, shader);
+ REPORTER_ASSERT(reporter, shader->isOpaque());
+ shader->unref();
+
+ // test 4: explicitly not opaque
+ bmp.setIsOpaque(false);
+ shader = SkShader::CreateBitmapShader(bmp,
+ SkShader::kClamp_TileMode, SkShader::kClamp_TileMode);
+ REPORTER_ASSERT(reporter, shader);
+ REPORTER_ASSERT(reporter, !shader->isOpaque());
+ shader->unref();
+
+}
+
+static void test_gradient(skiatest::Reporter* reporter)
+{
+ SkPoint pts[2];
+ pts[0].iset(0, 0);
+ pts[1].iset(1, 0);
+ SkColor colors[2];
+ SkScalar pos[2] = {SkIntToScalar(0), SkIntToScalar(1)};
+ int count = 2;
+ SkShader::TileMode mode = SkShader::kClamp_TileMode;
+
+ // test 1: all opaque
+ colors[0] = SkColorSetARGB(0xFF, 0, 0, 0);
+ colors[1] = SkColorSetARGB(0xFF, 0, 0, 0);
+ SkShader* grad = SkGradientShader::CreateLinear(pts, colors, pos, count,
+ mode);
+ REPORTER_ASSERT(reporter, grad);
+ REPORTER_ASSERT(reporter, grad->isOpaque());
+ grad->unref();
+
+ // test 2: all 0 alpha
+ colors[0] = SkColorSetARGB(0, 0, 0, 0);
+ colors[1] = SkColorSetARGB(0, 0, 0, 0);
+ grad = SkGradientShader::CreateLinear(pts, colors, pos, count, mode);
+ REPORTER_ASSERT(reporter, grad);
+ REPORTER_ASSERT(reporter, !grad->isOpaque());
+ grad->unref();
+
+ // test 3: one opaque, one transparent
+ colors[0] = SkColorSetARGB(0xFF, 0, 0, 0);
+ colors[1] = SkColorSetARGB(0x40, 0, 0, 0);
+ grad = SkGradientShader::CreateLinear(pts, colors, pos, count, mode);
+ REPORTER_ASSERT(reporter, grad);
+ REPORTER_ASSERT(reporter, !grad->isOpaque());
+ grad->unref();
+
+ // test 4: test 3, swapped
+ colors[0] = SkColorSetARGB(0x40, 0, 0, 0);
+ colors[1] = SkColorSetARGB(0xFF, 0, 0, 0);
+ grad = SkGradientShader::CreateLinear(pts, colors, pos, count, mode);
+ REPORTER_ASSERT(reporter, grad);
+ REPORTER_ASSERT(reporter, !grad->isOpaque());
+ grad->unref();
+}
+
+static void test_color(skiatest::Reporter* reporter)
+{
+ SkColorShader colorShader1(SkColorSetARGB(0,0,0,0));
+ REPORTER_ASSERT(reporter, !colorShader1.isOpaque());
+ SkColorShader colorShader2(SkColorSetARGB(0xFF,0,0,0));
+ REPORTER_ASSERT(reporter, colorShader2.isOpaque());
+ SkColorShader colorShader3(SkColorSetARGB(0x7F,0,0,0));
+ REPORTER_ASSERT(reporter, !colorShader3.isOpaque());
+
+ // with inherrited color, shader must declare itself as opaque,
+ // since lack of opacity will depend solely on the paint
+ SkColorShader colorShader4;
+ REPORTER_ASSERT(reporter, colorShader4.isOpaque());
+}
+
+static void test_shader_opacity(skiatest::Reporter* reporter)
+{
+ test_gradient(reporter);
+ test_color(reporter);
+ test_bitmap(reporter);
+}
+
+#include "TestClassDef.h"
+DEFINE_TESTCLASS("ShaderOpacity", ShaderOpacityTestClass, test_shader_opacity)