Convert SkPMFloat to [0,1] range and prune its API.

tests/PMFloatTest.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 "SkPMFloat.h"
 #include "Test.h"
 
 DEF_TEST(SkPMFloat, r) {
     // Test SkPMColor <-> SkPMFloat
     SkPMColor c = SkPreMultiplyColor(0xFFCC9933);
     SkPMFloat pmf(c);
-    REPORTER_ASSERT(r, SkScalarNearlyEqual(255.0f, pmf.a()));
-    REPORTER_ASSERT(r, SkScalarNearlyEqual(204.0f, pmf.r()));
-    REPORTER_ASSERT(r, SkScalarNearlyEqual(153.0f, pmf.g()));
-    REPORTER_ASSERT(r, SkScalarNearlyEqual( 51.0f, pmf.b()));
+    REPORTER_ASSERT(r, SkScalarNearlyEqual(255.0f, 255*pmf.a()));
+    REPORTER_ASSERT(r, SkScalarNearlyEqual(204.0f, 255*pmf.r()));
+    REPORTER_ASSERT(r, SkScalarNearlyEqual(153.0f, 255*pmf.g()));
+    REPORTER_ASSERT(r, SkScalarNearlyEqual( 51.0f, 255*pmf.b()));
     REPORTER_ASSERT(r, c == pmf.round());
 
     // Test rounding.
-    pmf = SkPMFloat(254.5f, 203.5f, 153.1f, 50.8f);
+    pmf = SkPMFloat(254.5f/255, 203.5f/255, 153.1f/255, 50.8f/255);
     REPORTER_ASSERT(r, c == pmf.round());
 
-    pmf = SkPMFloat(255.9f, 204.01f, 153.0f, -0.9f);
-    REPORTER_ASSERT(r, SkPreMultiplyColor(0xFFCC9900) == pmf.trunc());
-
-    // Test clamping.
-    SkPMFloat clamped(SkPMFloat(510.0f, 153.0f, 1.0f, -0.2f).roundClamp());
-    REPORTER_ASSERT(r, SkScalarNearlyEqual(255.0f, clamped.a()));
-    REPORTER_ASSERT(r, SkScalarNearlyEqual(153.0f, clamped.r()));
-    REPORTER_ASSERT(r, SkScalarNearlyEqual(  1.0f, clamped.g()));
-    REPORTER_ASSERT(r, SkScalarNearlyEqual(  0.0f, clamped.b()));
+    SkPMFloat clamped(SkPMFloat(510.0f/255, 153.0f/255, 1.0f/255, -0.2f/255).round());
+    REPORTER_ASSERT(r, SkScalarNearlyEqual(255.0f, 255*clamped.a()));
+    REPORTER_ASSERT(r, SkScalarNearlyEqual(153.0f, 255*clamped.r()));
+    REPORTER_ASSERT(r, SkScalarNearlyEqual(  1.0f, 255*clamped.g()));
+    REPORTER_ASSERT(r, SkScalarNearlyEqual(  0.0f, 255*clamped.b()));
 
     // Test SkPMFloat <-> Sk4f conversion.
     Sk4f fs = clamped;
     SkPMFloat scaled = fs * Sk4f(0.25f);
-    REPORTER_ASSERT(r, SkScalarNearlyEqual(63.75f, scaled.a()));
-    REPORTER_ASSERT(r, SkScalarNearlyEqual(38.25f, scaled.r()));
-    REPORTER_ASSERT(r, SkScalarNearlyEqual( 0.25f, scaled.g()));
-    REPORTER_ASSERT(r, SkScalarNearlyEqual( 0.00f, scaled.b()));
-
-    // Test 4-at-a-time conversions.
-    SkPMColor colors[4] = { 0xFF000000, 0xFFFF0000, 0xFF00FF00, 0xFF0000FF };
-    SkPMFloat floats[4];
-    SkPMFloat::From4PMColors(colors, floats+0, floats+1, floats+2, floats+3);
-
-    SkPMColor back[4];
-    SkPMFloat::RoundTo4PMColors(floats[0], floats[1], floats[2], floats[3], back);
-    for (int i = 0; i < 4; i++) {
-        REPORTER_ASSERT(r, back[i] == colors[i]);
-    }
-
-    SkPMFloat::RoundClampTo4PMColors(floats[0], floats[1], floats[2], floats[3], back);
-    for (int i = 0; i < 4; i++) {
-        REPORTER_ASSERT(r, back[i] == colors[i]);
-    }
+    REPORTER_ASSERT(r, SkScalarNearlyEqual(63.75f, 255*scaled.a()));
+    REPORTER_ASSERT(r, SkScalarNearlyEqual(38.25f, 255*scaled.r()));
+    REPORTER_ASSERT(r, SkScalarNearlyEqual( 0.25f, 255*scaled.g()));
+    REPORTER_ASSERT(r, SkScalarNearlyEqual( 0.00f, 255*scaled.b()));
 }