Basic error checking for debugger GL widget.

debugger/QT/SkGLWidget.cpp

 
 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkGLWidget.h"
@@ skipping 11 matching lines @@
 
 SkGLWidget::~SkGLWidget() {
     SkSafeUnref(fCurIntf);
     SkSafeUnref(fCurContext);
     SkSafeUnref(fGpuDevice);
     SkSafeUnref(fCanvas);
 }
 
 void SkGLWidget::initializeGL() {
     fCurIntf = GrGLCreateNativeInterface();
+    if (!fCurIntf) {
+        return;
+    }
     fCurContext = GrContext::Create(kOpenGL_GrBackend, (GrBackendContext) fCurIntf);
     GrBackendRenderTargetDesc desc = this->getDesc(this->width(), this->height());
     desc.fOrigin = kBottomLeft_GrSurfaceOrigin;
     GrRenderTarget* curRenderTarget = fCurContext->wrapBackendRenderTarget(desc);
     fGpuDevice = new SkGpuDevice(fCurContext, curRenderTarget);
     fCanvas = new SkCanvas(fGpuDevice);
     curRenderTarget->unref();
 
     glClearColor(1, 1, 1, 0);
     glClearStencil(0);
     glClear(GL_STENCIL_BUFFER_BIT);
 }
 
 void SkGLWidget::resizeGL(int w, int h) {
-    GrBackendRenderTargetDesc desc = this->getDesc(w, h);
-    desc.fOrigin = kBottomLeft_GrSurfaceOrigin;
-    GrRenderTarget* curRenderTarget = fCurContext->wrapBackendRenderTarget(desc);
-    SkSafeUnref(fGpuDevice);
-    SkSafeUnref(fCanvas);
-    fGpuDevice = new SkGpuDevice(fCurContext, curRenderTarget);
-    fCanvas = new SkCanvas(fGpuDevice);
+    if (fCurContext) {
+        GrBackendRenderTargetDesc desc = this->getDesc(w, h);
+        desc.fOrigin = kBottomLeft_GrSurfaceOrigin;
+        GrRenderTarget* curRenderTarget = fCurContext->wrapBackendRenderTarget(desc);
+        SkSafeUnref(fGpuDevice);
+        SkSafeUnref(fCanvas);
+        fGpuDevice = new SkGpuDevice(fCurContext, curRenderTarget);
+        fCanvas = new SkCanvas(fGpuDevice);
+    }
     fDebugger->resize(w, h);
     draw();
 }
 
 void SkGLWidget::paintGL() {
-    if (!this->isHidden()) {
+    if (!this->isHidden() && fCanvas) {
         fDebugger->draw(fCanvas);
         // TODO(chudy): Implement an optional flush button in Gui.
         fCanvas->flush();
         emit drawComplete();
     }
 }
 
 GrBackendRenderTargetDesc SkGLWidget::getDesc(int w, int h) {
     GrBackendRenderTargetDesc desc;
     desc.fWidth = SkScalarRound(this->width());
     desc.fHeight = SkScalarRound(this->height());
     desc.fConfig = kSkia8888_GrPixelConfig;
     GR_GL_GetIntegerv(fCurIntf, GR_GL_SAMPLES, &desc.fSampleCnt);
     GR_GL_GetIntegerv(fCurIntf, GR_GL_STENCIL_BITS, &desc.fStencilBits);
     GrGLint buffer;
     GR_GL_GetIntegerv(fCurIntf, GR_GL_FRAMEBUFFER_BINDING, &buffer);
     desc.fRenderTargetHandle = buffer;
 
     return desc;
 }
 
 #endif