From d494b09f554d470fc6411d0924879bbfb0cb0e95 Mon Sep 17 00:00:00 2001 From: "commit-bot@chromium.org" Date: Thu, 10 Oct 2013 20:13:51 +0000 Subject: Align SkLumaColorFilter with the spec. The spec requires the resulting RGB channels for LuminanceToAlpha to be 0 (and not just scaled by the luminance value): | R' | | 0 0 0 0 0 | | R | | G' | | 0 0 0 0 0 | | G | | B' | = | 0 0 0 0 0 | * | B | | A' | | 0.2125 0.7154 0.0721 0 0 | | A | | 1 | | 0 0 0 0 1 | | 1 | (http://www.w3.org/TR/2011/REC-SVG11-20110816/filters.html#feColorMatrixElement) This doesn't affect luminance masking (which depends only on the resulting alpha channel), but other color filter users may care about all color components. R=bsalomon@google.com, reed@google.com, robertphillips@google.com Author: fmalita@chromium.org Review URL: https://codereview.chromium.org/26467003 git-svn-id: http://skia.googlecode.com/svn/trunk@11713 2bbb7eff-a529-9590-31e7-b0007b416f81 --- tests/ColorFilterTest.cpp | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) (limited to 'tests/ColorFilterTest.cpp') diff --git a/tests/ColorFilterTest.cpp b/tests/ColorFilterTest.cpp index b333ad68f0..8c96d752fb 100644 --- a/tests/ColorFilterTest.cpp +++ b/tests/ColorFilterTest.cpp @@ -101,11 +101,14 @@ static void test_lumaColorFilter(skiatest::Reporter* reporter) { SkPMColor in, out; SkAutoTUnref lf(SkLumaColorFilter::Create()); - // Applying luma to white is a nop (luminance(white) == 1.0) + // Applying luma to white produces black with the same transparency. for (unsigned i = 0; i < 256; ++i) { in = SkPackARGB32(i, i, i, i); lf->filterSpan(&in, 1, &out); - REPORTER_ASSERT(reporter, out == in); + REPORTER_ASSERT(reporter, SkGetPackedA32(out) == i); + REPORTER_ASSERT(reporter, SkGetPackedR32(out) == 0); + REPORTER_ASSERT(reporter, SkGetPackedG32(out) == 0); + REPORTER_ASSERT(reporter, SkGetPackedB32(out) == 0); } // Applying luma to black yields transparent black (luminance(black) == 0) @@ -115,15 +118,15 @@ static void test_lumaColorFilter(skiatest::Reporter* reporter) { REPORTER_ASSERT(reporter, out == SK_ColorTRANSPARENT); } - // For general colors, a luma filter has an attenuating effect. + // For general colors, a luma filter generates black with an attenuated alpha channel. for (unsigned i = 1; i < 256; ++i) { in = SkPackARGB32(i, i, i / 2, i / 3); lf->filterSpan(&in, 1, &out); REPORTER_ASSERT(reporter, out != in); REPORTER_ASSERT(reporter, SkGetPackedA32(out) <= i); - REPORTER_ASSERT(reporter, SkGetPackedR32(out) <= i); - REPORTER_ASSERT(reporter, SkGetPackedG32(out) <= i / 2); - REPORTER_ASSERT(reporter, SkGetPackedB32(out) <= i / 3); + REPORTER_ASSERT(reporter, SkGetPackedR32(out) == 0); + REPORTER_ASSERT(reporter, SkGetPackedG32(out) == 0); + REPORTER_ASSERT(reporter, SkGetPackedB32(out) == 0); } } -- cgit v1.2.3