Added API for Bevel NormalSource.

gm/lightingshader.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 "gm.h"
 
 #include "SkBitmapProcShader.h"
@@ skipping 41 matching lines @@
 
         builder.add(SkLights::Light(SkColor3f::Make(1.0f, 1.0f, 1.0f),
                                     SkVector3::Make(SK_ScalarRoot2Over2,
                                                     0.0f,
                                                     SK_ScalarRoot2Over2)));
         builder.add(SkLights::Light(SkColor3f::Make(0.2f, 0.2f, 0.2f)));
 
         fLights = builder.finish();
     }
 
 protected:

[robertphillips, 2016/07/11 19:13:21]

Would it make sense to convert this to an enum of normal sources e.g.,
   kHemiNormalMap_Source
   ...
   kBevel_Source

?

We would then precompute and store sk_sp<SkNormalSource>'s in onOnceBeforeDraw.

[dvonbeck, 2016/07/13 14:23:37]

Can't do it. SkNormalSource's SkBitmapProcShader needs the local matrix to know
the coordinates from which to sample the normals.

     enum NormalMap {
         kHemi_NormalMap,
         kFrustum_NormalMap,
         kTetra_NormalMap,
 
         kLast_NormalMap = kTetra_NormalMap
     };
 
     static const int kNormalMapCount = kLast_NormalMap+1;
 
@@ skipping 32 matching lines @@
         sk_sp<SkShader> normalMap = SkMakeBitmapShader(fNormalMaps[mapType],
                 SkShader::kClamp_TileMode, SkShader::kClamp_TileMode, &matrix, nullptr);
         sk_sp<SkNormalSource> normalSource = SkNormalSource::MakeFromNormalMap(std::move(normalMap),
                                                                                ctm);
         paint.setShader(SkLightingShader::Make(std::move(diffuseShader), std::move(normalSource),
                                                fLights));
 
         canvas->drawRect(r, paint);
     }
 
+    void drawBevelRect(SkCanvas* canvas, const SkRect& r) {
+
+        SkRect bitmapBounds = SkRect::MakeIWH(fDiffuse.width(), fDiffuse.height());
+
+        SkMatrix matrix;
+        matrix.setRectToRect(bitmapBounds, r, SkMatrix::kFill_ScaleToFit);
+
+        SkPaint paint;

[robertphillips, 2016/07/11 19:13:21]

Add '\n'

[dvonbeck, 2016/07/13 14:23:37]

Done.

+        auto diffuseShader = SkBitmapProcShader::MakeBitmapShader(fDiffuse,
+                                                                  SkShader::kClamp_TileMode, SkShader::kClamp_TileMode, &matrix);
+        auto normalSource = SkNormalSource::MakeBevel(
+                SkNormalSource::BevelType::kLinear,
+                0.15f * SkIntToScalar(kTexSize),
+                0.2f * SkIntToScalar(kTexSize));
+        paint.setShader(SkLightingShader::Make(std::move(diffuseShader), std::move(normalSource),
+                                               fLights));
+
+        canvas->drawRect(r, paint);
+    }
+
     void onDraw(SkCanvas* canvas) override {
         SkMatrix m;
         SkRect r;
 
         {
             r = SkRect::MakeWH(SkIntToScalar(kTexSize), SkIntToScalar(kTexSize));
             this->drawRect(canvas, r, kHemi_NormalMap);
 
             canvas->save();
             m.setRotate(45.0f, r.centerX(), r.centerY());
             m.postTranslate(kGMSize/2.0f - kTexSize/2.0f, 0.0f);
             canvas->setMatrix(m);
             this->drawRect(canvas, r, kHemi_NormalMap);
             canvas->restore();
         }
 
         {
             r.offset(kGMSize - kTexSize, 0);
             this->drawRect(canvas, r, kFrustum_NormalMap);
 
             canvas->save();
             m.setRotate(45.0f, r.centerX(), r.centerY());
             m.postTranslate(0.0f, kGMSize/2.0f - kTexSize/2.0f);
             canvas->setMatrix(m);
-            this->drawRect(canvas, r, kFrustum_NormalMap);
+            this->drawBevelRect(canvas, r);
             canvas->restore();
         }
 
         {
             r.offset(0, kGMSize - kTexSize);
             this->drawRect(canvas, r, kTetra_NormalMap);
 
             canvas->save();
             m.setRotate(45.0f, r.centerX(), r.centerY());
             m.postTranslate(-kGMSize/2.0f + kTexSize/2.0f, 0.0f);
@@ skipping 24 matching lines @@
 
     sk_sp<SkLights> fLights;
 
     typedef GM INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 DEF_GM(return new LightingShaderGM;)
 }