move Coeff into blendmode

Bug: skia:
Change-Id: Ib4f3398b0cdc6b0f575f6db80d2ce0bf9666f077
Reviewed-on: https://skia-review.googlesource.com/18843
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>

1 files changed, 104 insertions, 0 deletions

diff --git a/src/core/SkBlendMode.cpp b/src/core/SkBlendMode.cpp
new file mode 100644
index 0000000000..d7ebfb8f8e
--- /dev/null
+++ b/src/core/SkBlendMode.cpp
@@ -0,0 +1,104 @@
+/*
+ * Copyright 2017 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkBlendModePriv.h"
+#include "SkRasterPipeline.h"
+
+bool SkBlendMode_CanOverflow(SkBlendMode mode) {
+    return mode == SkBlendMode::kPlus;
+}
+
+bool SkBlendMode_SupportsCoverageAsAlpha(SkBlendMode mode) {
+    switch (mode) {
+        case SkBlendMode::kDst:
+        case SkBlendMode::kSrcOver:
+        case SkBlendMode::kDstOver:
+        case SkBlendMode::kDstOut:
+        case SkBlendMode::kSrcATop:
+        case SkBlendMode::kXor:
+        case SkBlendMode::kPlus:
+            return true;
+        default:
+            break;
+    }
+    return false;
+}
+
+struct CoeffRec {
+    SkBlendModeCoeff    fSrc;
+    SkBlendModeCoeff    fDst;
+};
+
+const CoeffRec gCoeffs[] = {
+    { SkBlendModeCoeff::kZero,    SkBlendModeCoeff::kZero },
+    { SkBlendModeCoeff::kOne,     SkBlendModeCoeff::kZero },
+    { SkBlendModeCoeff::kZero,    SkBlendModeCoeff::kOne  },
+    { SkBlendModeCoeff::kOne,     SkBlendModeCoeff::kISA  },
+    { SkBlendModeCoeff::kIDA,     SkBlendModeCoeff::kOne  },
+    { SkBlendModeCoeff::kDA,      SkBlendModeCoeff::kZero },
+    { SkBlendModeCoeff::kZero,    SkBlendModeCoeff::kSA   },
+    { SkBlendModeCoeff::kIDA,     SkBlendModeCoeff::kZero },
+    { SkBlendModeCoeff::kZero,    SkBlendModeCoeff::kISA  },
+    { SkBlendModeCoeff::kDA,      SkBlendModeCoeff::kISA  },
+    { SkBlendModeCoeff::kIDA,     SkBlendModeCoeff::kSA   },
+    { SkBlendModeCoeff::kIDA,     SkBlendModeCoeff::kISA  },
+
+    { SkBlendModeCoeff::kOne,     SkBlendModeCoeff::kOne  },
+    { SkBlendModeCoeff::kZero,    SkBlendModeCoeff::kSC   },
+    { SkBlendModeCoeff::kOne,     SkBlendModeCoeff::kISC  },    // screen
+};
+
+bool SkBlendMode_AsCoeff(SkBlendMode mode, SkBlendModeCoeff* src, SkBlendModeCoeff* dst) {
+    if (mode > SkBlendMode::kScreen) {
+        return false;
+    }
+    if (src) {
+        *src = gCoeffs[static_cast<int>(mode)].fSrc;
+    }
+    if (dst) {
+        *dst = gCoeffs[static_cast<int>(mode)].fDst;
+    }
+    return true;
+}
+
+void SkBlendMode_AppendStages(SkBlendMode mode, SkRasterPipeline* p) {
+    auto stage = SkRasterPipeline::srcover;
+    switch (mode) {
+        case SkBlendMode::kClear:    stage = SkRasterPipeline::clear; break;
+        case SkBlendMode::kSrc:      return;  // This stage is a no-op.
+        case SkBlendMode::kDst:      stage = SkRasterPipeline::move_dst_src; break;
+        case SkBlendMode::kSrcOver:  stage = SkRasterPipeline::srcover; break;
+        case SkBlendMode::kDstOver:  stage = SkRasterPipeline::dstover; break;
+        case SkBlendMode::kSrcIn:    stage = SkRasterPipeline::srcin; break;
+        case SkBlendMode::kDstIn:    stage = SkRasterPipeline::dstin; break;
+        case SkBlendMode::kSrcOut:   stage = SkRasterPipeline::srcout; break;
+        case SkBlendMode::kDstOut:   stage = SkRasterPipeline::dstout; break;
+        case SkBlendMode::kSrcATop:  stage = SkRasterPipeline::srcatop; break;
+        case SkBlendMode::kDstATop:  stage = SkRasterPipeline::dstatop; break;
+        case SkBlendMode::kXor:      stage = SkRasterPipeline::xor_; break;
+        case SkBlendMode::kPlus:     stage = SkRasterPipeline::plus_; break;
+        case SkBlendMode::kModulate: stage = SkRasterPipeline::modulate; break;
+
+        case SkBlendMode::kScreen:     stage = SkRasterPipeline::screen; break;
+        case SkBlendMode::kOverlay:    stage = SkRasterPipeline::overlay; break;
+        case SkBlendMode::kDarken:     stage = SkRasterPipeline::darken; break;
+        case SkBlendMode::kLighten:    stage = SkRasterPipeline::lighten; break;
+        case SkBlendMode::kColorDodge: stage = SkRasterPipeline::colordodge; break;
+        case SkBlendMode::kColorBurn:  stage = SkRasterPipeline::colorburn; break;
+        case SkBlendMode::kHardLight:  stage = SkRasterPipeline::hardlight; break;
+        case SkBlendMode::kSoftLight:  stage = SkRasterPipeline::softlight; break;
+        case SkBlendMode::kDifference: stage = SkRasterPipeline::difference; break;
+        case SkBlendMode::kExclusion:  stage = SkRasterPipeline::exclusion; break;
+        case SkBlendMode::kMultiply:   stage = SkRasterPipeline::multiply; break;
+
+        case SkBlendMode::kHue:        stage = SkRasterPipeline::hue; break;
+        case SkBlendMode::kSaturation: stage = SkRasterPipeline::saturation; break;
+        case SkBlendMode::kColor:      stage = SkRasterPipeline::color; break;
+        case SkBlendMode::kLuminosity: stage = SkRasterPipeline::luminosity; break;
+    }
+    p->append(stage);
+}