SkCanvas interface for drawing a patch.

gm/patch.cpp

 
 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 // This test only works with the GPU backend.
 
 #include "gm.h"
 
 #if SK_SUPPORT_GPU
 
 #include "GrContext.h"
 #include "GrTest.h"
+#include "SkPatch.h"
 
-#include "SkPatch.h"
+static void draw_control_points(SkCanvas* canvas, SkPatch& patch, SkPaint& paint) {
+    //draw control points
+    SkPaint copy(paint);
+    SkPoint bottom[4];
+    patch.getBottomPoints(bottom);
+    SkPoint top[4];
+    patch.getTopPoints(top);
+    SkPoint left[4];
+    patch.getLeftPoints(left);
+    SkPoint right[4];
+    patch.getRightPoints(right);
+
+    copy.setColor(SK_ColorBLACK);
+    copy.setStrokeWidth(0.5);
+    SkPoint corners[4] = { bottom[0], bottom[3], top[0], top[3] };
+    canvas->drawPoints(SkCanvas::kLines_PointMode, 4, bottom, copy);
+    canvas->drawPoints(SkCanvas::kLines_PointMode, 2, bottom+1, copy);
+    canvas->drawPoints(SkCanvas::kLines_PointMode, 4, top, copy);
+    canvas->drawPoints(SkCanvas::kLines_PointMode, 4, left, copy);
+    canvas->drawPoints(SkCanvas::kLines_PointMode, 4, right, copy);
+
+    canvas->drawPoints(SkCanvas::kLines_PointMode, 2, top+1, copy);
+    canvas->drawPoints(SkCanvas::kLines_PointMode, 2, left+1, copy);
+    canvas->drawPoints(SkCanvas::kLines_PointMode, 2, right+1, copy);
+
+    copy.setStrokeWidth(2);
+
+    copy.setColor(SK_ColorRED);
+    canvas->drawPoints(SkCanvas::kPoints_PointMode, 4, corners, copy);
+
+    copy.setColor(SK_ColorBLUE);
+    canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, bottom+1, copy);
+
+    copy.setColor(SK_ColorCYAN);
+    canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, top+1, copy);
+
+    copy.setColor(SK_ColorYELLOW);
+    canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, left+1, copy);
+
+    copy.setColor(SK_ColorGREEN);
+    canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, right+1, copy);
+}
+
+static void draw_random_patch(SkPoint points[12], SkColor colors[4], SkCanvas* canvas,
+                              SkPaint& paint, SkRandom* rnd) {
+    SkPoint ptsCpy[12];
+    memcpy(ptsCpy, points, 12 * sizeof(SkPoint));
+    for (int i = 0; i < 5; i++) {
+        int index = rnd->nextRangeU(0, 11);
+        SkScalar dx = rnd->nextRangeScalar(-50, 50), dy = rnd->nextRangeScalar(-50, 50);
+        ptsCpy[index].offset(dx, dy);
+    }
+    SkPatch patch(ptsCpy, colors);
+    canvas->drawPatch(patch, paint);
+    draw_control_points(canvas, patch, paint);
+}
 
 namespace skiagm {
 /**
  * This GM draws a SkPatch.
  */
 class SkPatchGM : public GM {
+    
 public:
     SkPatchGM() {
         this->setBGColor(0xFFFFFFFF);
     }
 
 protected:
     virtual SkString onShortName() SK_OVERRIDE {
         return SkString("patch_primitive");
     }
 
     virtual SkISize onISize() SK_OVERRIDE {
         return SkISize::Make(800, 800);
     }
 
     virtual uint32_t onGetFlags() const SK_OVERRIDE {
-        return kGPUOnly_Flag;
+        return kSkipTiled_Flag | kSkipPipe_Flag | kSkipPicture_Flag;
     }
-
-
+    
     virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
-
+        
         SkPaint paint;
         SkColor colors[4] = {
             SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorCYAN
         };
-        SkPoint points[] = {
-            {100,100},{130,50},{500,70}, {650,60},
-            {350,125},{490,555},{600,700},
-            {515,595},{140,550},{110,590},
-            {125,400},{70,150}
-            
+        SkPoint points[12] = {
+            {50,50},{75,20},{125,80}, {150,50},
+            {120,75},{180,125},{150,150},
+            {125,120},{75,180},{50,150},
+            {20,125},{80,75}
         };
-
-        SkPatch coons(points, colors);
         
-        SkPatch::VertexData data;
-        coons.getVertexData(&data, 10);
-
-        canvas->drawVertices(SkCanvas::kTriangles_VertexMode,data.fVertexCount,
-            data.fPoints, data.fTexCoords, data.fColors, NULL, data.fIndices,
-            data.fIndexCount, paint);
-
-        //draw control points
-        SkPoint bottom[4];
-        coons.getBottomPoints(bottom);
-        SkPoint top[4];
-        coons.getTopPoints(top);
-        SkPoint left[4];
-        coons.getLeftPoints(left);
-        SkPoint right[4];
-        coons.getRightPoints(right);
-
-        SkPoint corners[4] = { bottom[0], bottom[3], top[0], top[3] };
-        canvas->drawPoints(SkCanvas::kLines_PointMode, 4, bottom, paint);
-        canvas->drawPoints(SkCanvas::kLines_PointMode, 2, bottom+1, paint);
-        canvas->drawPoints(SkCanvas::kLines_PointMode, 4, top, paint);
-        canvas->drawPoints(SkCanvas::kLines_PointMode, 4, left, paint);
-        canvas->drawPoints(SkCanvas::kLines_PointMode, 4, right, paint);
-
-        canvas->drawPoints(SkCanvas::kLines_PointMode, 2, top+1, paint);
-        canvas->drawPoints(SkCanvas::kLines_PointMode, 2, left+1, paint);
-        canvas->drawPoints(SkCanvas::kLines_PointMode, 2, right+1, paint);
-
-        paint.setStrokeWidth(10);
-
-        paint.setColor(SK_ColorRED);
-        canvas->drawPoints(SkCanvas::kPoints_PointMode, 4, corners, paint);
-
-        paint.setColor(SK_ColorBLUE);
-        canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, bottom+1, paint);
-
-        paint.setColor(SK_ColorCYAN);
-        canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, top+1, paint);
-
-        paint.setColor(SK_ColorYELLOW);
-        canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, left+1, paint);
-
-        paint.setColor(SK_ColorGREEN);
-        canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, right+1, paint);
+        SkRandom rnd;
+        SkScalar scale = 0.5f;
+        canvas->save();
+        for (SkScalar x = 0; x < 4; x++) {
+            canvas->save();
+            canvas->scale(scale * (x + 1), scale * (x + 1));
+            canvas->translate(x * 100, 0);
+            draw_random_patch(points, colors, canvas, paint, &rnd);
+            canvas->restore();
+        }
+        canvas->translate(0, 270);
+        SkScalar skew = 0.1f;
+        for (SkScalar x = 0; x < 4; x++) {
+            canvas->save();
+            canvas->scale(scale * (x + 1), scale * (x + 1));
+            canvas->skew(skew * (x + 1), skew * (x + 1));
+            canvas->translate(x * 100, 0);
+            draw_random_patch(points, colors, canvas, paint, &rnd);
+            canvas->restore();
+        }
+        canvas->restore();
     }
 
 private:
     typedef GM INHERITED;
 };
 
-DEF_GM( return SkNEW(SkPatchGM); )
+DEF_GM(return SkNEW(SkPatchGM); )
 
 }
 
 #endif