float components in xfermodes

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1623483002

TBR=mtklein

Review URL: https://codereview.chromium.org/1634273002

2 files changed, 79 insertions, 8 deletions

diff --git a/gm/color4f.cpp b/gm/color4f.cpp
new file mode 100644
index 0000000000..98ce0824cc
--- /dev/null
+++ b/gm/color4f.cpp
@@ -0,0 +1,69 @@
+/*
+ * 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 "gm.h"
+#include "SkCanvas.h"
+#include "SkColorPriv.h"
+#include "SkShader.h"
+#include "SkSurface.h"
+
+#include "SkColorMatrixFilter.h"
+#include "SkGradientShader.h"
+
+static SkShader* make_opaque_color() {
+    return SkShader::CreateColorShader(0xFFFF0000);
+}
+
+static SkShader* make_alpha_color() {
+    return SkShader::CreateColorShader(0x80FF0000);
+}
+
+static SkColorFilter* make_cf_null() {
+    return nullptr;
+}
+
+static SkColorFilter* make_cf0() {
+    SkColorMatrix cm;
+    cm.setSaturation(0.75f);
+    return SkColorMatrixFilter::Create(cm);
+}
+
+static void draw_into_canvas(SkCanvas* canvas) {
+    const SkRect r = SkRect::MakeWH(100, 100);
+    SkShader* (*shaders[])() { make_opaque_color, make_alpha_color };
+    SkColorFilter* (*filters[])() { make_cf_null, make_cf0 };
+    
+    SkPaint paint;
+    for (auto shProc : shaders) {
+        paint.setShader(shProc())->unref();
+        for (auto cfProc : filters) {
+            SkSafeUnref(paint.setColorFilter(cfProc()));
+            canvas->drawRect(r, paint);
+            canvas->translate(120, 0);
+        }
+    }
+}
+
+DEF_SIMPLE_GM(color4f, canvas, 510, 250) {
+    canvas->translate(20, 20);
+
+    SkPaint bg;
+    // need the target to be opaque, so we can draw it to the screen
+    // even if it holds sRGB values.
+    bg.setColor(0xFFFFFFFF);
+
+    SkColorProfileType const profiles[] { kLinear_SkColorProfileType, kSRGB_SkColorProfileType };
+    for (auto profile : profiles) {
+        const SkImageInfo info = SkImageInfo::Make(500, 100, kN32_SkColorType, kPremul_SkAlphaType,
+                                                   profile);
+        SkAutoTUnref<SkSurface> surface(SkSurface::NewRaster(info));
+        surface->getCanvas()->drawPaint(bg);
+        draw_into_canvas(surface->getCanvas());
+        surface->draw(canvas, 0, 0, nullptr);
+        canvas->translate(0, 120);
+    }
+}
diff --git a/gm/xfer4f.cpp b/gm/xfer4f.cpp
index 1951fdbde2..b74b6e0685 100644
--- a/gm/xfer4f.cpp
+++ b/gm/xfer4f.cpp
@@ -8,7 +8,7 @@
 #include "gm.h"
 #include "SkCanvas.h"
 #include "SkImageInfo.h"
-#include "SkXfer4f.h"
+#include "SkXfermode.h"
 
 static void draw_rect(SkCanvas* canvas, const SkRect& r, SkColor c, SkColorProfileType profile) {
     const SkIRect ir = r.round();
@@ -21,26 +21,28 @@ static void draw_rect(SkCanvas* canvas, const SkRect& r, SkColor c, SkColorProfi
 
     uint32_t flags = 0;
     if (SkColorGetA(c) == 0xFF) {
-        flags |= kSrcIsOpaque_SkXfer4fFlag;
+        flags |= SkXfermode::kSrcIsOpaque_PM4fFlag;
     }
     if (kSRGB_SkColorProfileType == profile) {
-        flags |= kDstIsSRGB_SkXfer4fFlag;
+        flags |= SkXfermode::kDstIsSRGB_PM4fFlag;
     }
 
-    const SkPM4f src = SkPM4f::FromPMColor(SkPreMultiplyColor(c));
-    auto proc1 = SkPM4fXfer1ProcFactory(SkXfermode::kSrcOver_Mode, flags);
+    const SkXfermode::PM4fState state { nullptr, flags };
+
+    const SkPM4f src = SkColor4f::FromColor(c).premul();
+    auto proc1 = SkXfermode::GetPM4fProc1(SkXfermode::kSrcOver_Mode, flags);
     for (int y = 0; y < ir.height()/2; ++y) {
-        proc1(pm.writable_addr32(0, y), src, ir.width());
+        proc1(state, pm.writable_addr32(0, y), src, ir.width(), nullptr);
     }
 
     SkPM4f srcRow[1000];
     for (int i = 0; i < ir.width(); ++i) {
         srcRow[i] = src;
     }
-    auto procN = SkPM4fXferNProcFactory(SkXfermode::kSrcOver_Mode, flags);
+    auto procN = SkXfermode::GetPM4fProcN(SkXfermode::kSrcOver_Mode, flags);
     // +1 to skip a row, so we can see the boundary between proc1 and procN
     for (int y = ir.height()/2 + 1; y < ir.height(); ++y) {
-        procN(pm.writable_addr32(0, y), srcRow, ir.width());
+        procN(state, pm.writable_addr32(0, y), srcRow, ir.width(), nullptr);
     }
 
     canvas->drawBitmap(bm, r.left(), r.top(), nullptr);