Virtualize SkGLContext with subclasses SkNativeGLContext and SkMesaGLContext, allow both in gm
Review URL: http://codereview.appspot.com/5307045/
git-svn-id: http://skia.googlecode.com/svn/trunk@2499 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/unix/SkNativeGLContext_unix.cpp b/src/gpu/unix/SkNativeGLContext_unix.cpp
new file mode 100644
index 0000000..870ff45
--- /dev/null
+++ b/src/gpu/unix/SkNativeGLContext_unix.cpp
@@ -0,0 +1,245 @@
+
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#include "SkNativeGLContext.h"
+
+#include <GL/glu.h>
+
+
+static bool ctxErrorOccurred = false;
+static int ctxErrorHandler(Display *dpy, XErrorEvent *ev) {
+ ctxErrorOccurred = true;
+ return 0;
+}
+
+SkNativeGLContext::SkNativeGLContext()
+ : fContext(NULL)
+ , fDisplay(NULL)
+ , fPixmap(0)
+ , fGlxPixmap(0) {
+}
+
+SkNativeGLContext::~SkNativeGLContext() {
+ this->destroyGLContext();
+}
+
+void SkNativeGLContext::destroyGLContext() {
+ if (fDisplay) {
+ glXMakeCurrent(fDisplay, 0, 0);
+
+ if (fContext) {
+ glXDestroyContext(fDisplay, fContext);
+ fContext = NULL;
+ }
+
+ if (fGlxPixmap) {
+ glXDestroyGLXPixmap(fDisplay, fGlxPixmap);
+ fGlxPixmap = 0;
+ }
+
+ if (fPixmap) {
+ XFreePixmap(fDisplay, fPixmap);
+ fPixmap = 0;
+ }
+
+ XCloseDisplay(fDisplay);
+ fDisplay = NULL;
+ }
+}
+
+const GrGLInterface* SkNativeGLContext::createGLContext() {
+ fDisplay = XOpenDisplay(0);
+
+ if (!fDisplay) {
+ SkDebugf("Failed to open X display.\n");
+ this->destroyGLContext();
+ return NULL;
+ }
+
+ // Get a matching FB config
+ static int visual_attribs[] = {
+ GLX_X_RENDERABLE , True,
+ GLX_DRAWABLE_TYPE , GLX_PIXMAP_BIT,
+ None
+ };
+
+ int glx_major, glx_minor;
+
+ // FBConfigs were added in GLX version 1.3.
+ if (!glXQueryVersion(fDisplay, &glx_major, &glx_minor) ||
+ ( (glx_major == 1) && (glx_minor < 3) ) || (glx_major < 1))
+ {
+ SkDebugf("Invalid GLX version.");
+ this->destroyGLContext();
+ return NULL;
+ }
+
+ //SkDebugf("Getting matching framebuffer configs.\n");
+ int fbcount;
+ GLXFBConfig *fbc = glXChooseFBConfig(fDisplay, DefaultScreen(fDisplay),
+ visual_attribs, &fbcount);
+ if (!fbc) {
+ SkDebugf("Failed to retrieve a framebuffer config.\n");
+ this->destroyGLContext();
+ return NULL;
+ }
+ //SkDebugf("Found %d matching FB configs.\n", fbcount);
+
+ // Pick the FB config/visual with the most samples per pixel
+ //SkDebugf("Getting XVisualInfos.\n");
+ int best_fbc = -1, worst_fbc = -1, best_num_samp = -1, worst_num_samp = 999;
+
+ int i;
+ for (i = 0; i < fbcount; ++i) {
+ XVisualInfo *vi = glXGetVisualFromFBConfig(fDisplay, fbc[i]);
+ if (vi) {
+ int samp_buf, samples;
+ glXGetFBConfigAttrib(fDisplay, fbc[i], GLX_SAMPLE_BUFFERS, &samp_buf);
+ glXGetFBConfigAttrib(fDisplay, fbc[i], GLX_SAMPLES, &samples);
+
+ //SkDebugf(" Matching fbconfig %d, visual ID 0x%2x: SAMPLE_BUFFERS = %d,"
+ // " SAMPLES = %d\n",
+ // i, (unsigned int)vi->visualid, samp_buf, samples);
+
+ if (best_fbc < 0 || (samp_buf && samples > best_num_samp))
+ best_fbc = i, best_num_samp = samples;
+ if (worst_fbc < 0 || !samp_buf || samples < worst_num_samp)
+ worst_fbc = i, worst_num_samp = samples;
+ }
+ XFree(vi);
+ }
+
+ GLXFBConfig bestFbc = fbc[best_fbc];
+
+ // Be sure to free the FBConfig list allocated by glXChooseFBConfig()
+ XFree(fbc);
+
+ // Get a visual
+ XVisualInfo *vi = glXGetVisualFromFBConfig(fDisplay, bestFbc);
+ //SkDebugf("Chosen visual ID = 0x%x\n", (unsigned int)vi->visualid);
+
+ fPixmap = XCreatePixmap(fDisplay, RootWindow(fDisplay, vi->screen), 10, 10, vi->depth);
+
+ if (!fPixmap) {
+ SkDebugf("Failed to create pixmap.\n");
+ this->destroyGLContext();
+ return NULL;
+ }
+
+ fGlxPixmap = glXCreateGLXPixmap(fDisplay, vi, fPixmap);
+
+ // Done with the visual info data
+ XFree(vi);
+
+ // Create the context
+
+ // Install an X error handler so the application won't exit if GL 3.0
+ // context allocation fails.
+ //
+ // Note this error handler is global.
+ // All display connections in all threads of a process use the same
+ // error handler, so be sure to guard against other threads issuing
+ // X commands while this code is running.
+ ctxErrorOccurred = false;
+ int (*oldHandler)(Display*, XErrorEvent*) =
+ XSetErrorHandler(&ctxErrorHandler);
+
+ // Get the default screen's GLX extension list
+ const char *glxExts = glXQueryExtensionsString(
+ fDisplay, DefaultScreen(fDisplay)
+ );
+ // Check for the GLX_ARB_create_context extension string and the function.
+ // If either is not present, use GLX 1.3 context creation method.
+ if (!gluCheckExtension(
+ reinterpret_cast<const GLubyte*>("GLX_ARB_create_context")
+ , reinterpret_cast<const GLubyte*>(glxExts)))
+ {
+ //SkDebugf("GLX_ARB_create_context not found."
+ // " Using old-style GLX context.\n");
+ fContext = glXCreateNewContext(fDisplay, bestFbc, GLX_RGBA_TYPE, 0, True);
+
+ } else {
+ //SkDebugf("Creating context.\n");
+
+ PFNGLXCREATECONTEXTATTRIBSARBPROC glXCreateContextAttribsARB =
+ (PFNGLXCREATECONTEXTATTRIBSARBPROC) glXGetProcAddressARB((GrGLubyte*)"glXCreateContextAttribsARB");
+ int context_attribs[] = {
+ GLX_CONTEXT_MAJOR_VERSION_ARB, 3,
+ GLX_CONTEXT_MINOR_VERSION_ARB, 0,
+ //GLX_CONTEXT_FLAGS_ARB , GLX_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB,
+ None
+ };
+ fContext = glXCreateContextAttribsARB(
+ fDisplay, bestFbc, 0, True, context_attribs
+ );
+
+ // Sync to ensure any errors generated are processed.
+ XSync(fDisplay, False);
+ if (!ctxErrorOccurred && fContext) {
+ //SkDebugf( "Created GL 3.0 context.\n" );
+ } else {
+ // Couldn't create GL 3.0 context.
+ // Fall back to old-style 2.x context.
+ // When a context version below 3.0 is requested,
+ // implementations will return the newest context version compatible
+ // with OpenGL versions less than version 3.0.
+
+ // GLX_CONTEXT_MAJOR_VERSION_ARB = 1
+ context_attribs[1] = 1;
+ // GLX_CONTEXT_MINOR_VERSION_ARB = 0
+ context_attribs[3] = 0;
+
+ ctxErrorOccurred = false;
+
+ //SkDebugf("Failed to create GL 3.0 context."
+ // " Using old-style GLX context.\n");
+ fContext = glXCreateContextAttribsARB(
+ fDisplay, bestFbc, 0, True, context_attribs
+ );
+ }
+ }
+
+ // Sync to ensure any errors generated are processed.
+ XSync(fDisplay, False);
+
+ // Restore the original error handler
+ XSetErrorHandler(oldHandler);
+
+ if (ctxErrorOccurred || !fContext) {
+ SkDebugf("Failed to create an OpenGL context.\n");
+ this->destroyGLContext();
+ return NULL;
+ }
+
+ // Verify that context is a direct context
+ if (!glXIsDirect(fDisplay, fContext)) {
+ //SkDebugf("Indirect GLX rendering context obtained.\n");
+ } else {
+ //SkDebugf("Direct GLX rendering context obtained.\n");
+ }
+
+ //SkDebugf("Making context current.\n");
+ if (!glXMakeCurrent(fDisplay, fGlxPixmap, fContext)) {
+ SkDebugf("Could not set the context.\n");
+ this->destroyGLContext();
+ return NULL;
+ }
+
+ const GrGLInterface* interface = GrGLCreateNativeInterface();
+ if (!interface) {
+ SkDebugf("Failed to create gl interface");
+ this->destroyGLContext();
+ return NULL;
+ }
+ return interface;
+}
+
+void SkNativeGLContext::makeCurrent() const {
+ if (!glXMakeCurrent(fDisplay, fGlxPixmap, fContext)) {
+ SkDebugf("Could not set the context.\n");
+ }
+}