Use common display initialization logic for Unix

src/views/unix/SkOSWindow_Unix.cpp

Index: src/views/unix/SkOSWindow_Unix.cpp
diff --git a/src/views/unix/SkOSWindow_Unix.cpp b/src/views/unix/SkOSWindow_Unix.cpp
index 4d4b628bfb61e50e79d3f27253e1e6feadaae392..0c8850674e0235d8a1cd25a1757b43b9f02e3a38 100644
--- a/src/views/unix/SkOSWindow_Unix.cpp
+++ b/src/views/unix/SkOSWindow_Unix.cpp
@@ -14,6 +14,8 @@
 
 #include "SkWindow.h"
 
+#include "gl/glx/GrNativeDisplay_glx.h"
+
 #include "SkBitmap.h"
 #include "SkCanvas.h"
 #include "SkColor.h"
@@ -82,42 +84,46 @@ void SkOSWindow::initWindow(int requestedMSAASampleCount, AttachmentInfo* info)
         SkDebugf("Could not open an X Display");
         return;
     }
-    // Attempt to create a window that supports GL
-    GLint att[] = {
-        GLX_RGBA,
+

[robertphillips, 2015/10/16 14:54:40]

static const int attrs[] ?

+    int att[] = {
         GLX_DEPTH_SIZE, 24,
-        GLX_DOUBLEBUFFER,
+        GLX_DOUBLEBUFFER, true,

[robertphillips, 2015/10/16 14:54:40]

Don't we need these stencil settings in the other location too ?

         GLX_STENCIL_SIZE, 8,
         None
     };
-    SkASSERT(nullptr == fVi);
-    if (requestedMSAASampleCount > 0) {
-        static const GLint kAttCount = SK_ARRAY_COUNT(att);
-        GLint msaaAtt[kAttCount + 4];
-        memcpy(msaaAtt, att, sizeof(att));
-        SkASSERT(None == msaaAtt[kAttCount - 1]);
-        msaaAtt[kAttCount - 1] = GLX_SAMPLE_BUFFERS_ARB;
-        msaaAtt[kAttCount + 0] = 1;
-        msaaAtt[kAttCount + 1] = GLX_SAMPLES_ARB;
-        msaaAtt[kAttCount + 2] = requestedMSAASampleCount;
-        msaaAtt[kAttCount + 3] = None;
-        fVi = glXChooseVisual(dsp, DefaultScreen(dsp), msaaAtt);
-        fMSAASampleCount = requestedMSAASampleCount;
-    }
-    if (nullptr == fVi) {
-        fVi = glXChooseVisual(dsp, DefaultScreen(dsp), att);
-        fMSAASampleCount = 0;
-    }
 
-    if (fVi) {
+    GLXFBConfig bestFbConfig;
+    if (!GrNativeDisplay::Initialize(att, fUnixWindow.fDisplay, &bestFbConfig)) {
+        if (info) {
+            info->fSampleCount = 0;
+            info->fStencilBits = 0;
+        }
+        // Create a simple window instead.  We will not be able to show GL
+        fUnixWindow.fWin = XCreateSimpleWindow(dsp,
+                                               DefaultRootWindow(dsp),
+                                               0, 0,  // x, y
+                                               WIDTH, HEIGHT,
+                                               0,     // border width
+                                               0,     // border value
+                                               0);    // background value
+    } else {
+        glXGetConfig(dsp, fVi, GLX_SAMPLES_ARB, &fMSAASampleCount);
+        if (fMSAASampleCount < requestedMSAASampleCount) {
+            SkDebugf("Requested samples exceeds the maximum allowed on this platform\n");
+        }
+
         if (info) {

[robertphillips, 2015/10/16 14:54:40]

Shouldn't this be requestedMSAASampleCount ?

-            glXGetConfig(dsp, fVi, GLX_SAMPLES_ARB, &info->fSampleCount);
+            info->fSampleCount = fMSAASampleCount;
             glXGetConfig(dsp, fVi, GLX_STENCIL_SIZE, &info->fStencilBits);
         }
+
+        fVi = glXGetVisualFromFBConfig(fUnixWindow.fDisplay, bestFbConfig);
+        SkASSERT(fVi);
+
         Colormap colorMap = XCreateColormap(dsp,
                                             RootWindow(dsp, fVi->screen),
                                             fVi->visual,
-                                             AllocNone);
+                                            AllocNone);
         XSetWindowAttributes swa;
         swa.colormap = colorMap;
         swa.event_mask = EVENT_MASK;
@@ -131,20 +137,9 @@ void SkOSWindow::initWindow(int requestedMSAASampleCount, AttachmentInfo* info)
                                          fVi->visual,
                                          CWEventMask | CWColormap,
                                          &swa);
-    } else {
-        if (info) {
-            info->fSampleCount = 0;
-            info->fStencilBits = 0;
-        }
-        // Create a simple window instead.  We will not be able to show GL
-        fUnixWindow.fWin = XCreateSimpleWindow(dsp,
-                                               DefaultRootWindow(dsp),
-                                               0, 0,  // x, y
-                                               WIDTH, HEIGHT,
-                                               0,     // border width
-                                               0,     // border value
-                                               0);    // background value
+
     }
+
     this->mapWindowAndWait();
     fUnixWindow.fGc = XCreateGC(dsp, fUnixWindow.fWin, 0, nullptr);
 }