1 files changed, 67 insertions, 0 deletions
diff --git a/platform/default/headless_backend_glx.cpp b/platform/default/headless_backend_glx.cpp
new file mode 100644
index 0000000000..bbfd19345b
--- /dev/null
+++ b/platform/default/headless_backend_glx.cpp
@@ -0,0 +1,67 @@
+#include <mbgl/platform/default/headless_backend.hpp>
+#include <mbgl/platform/default/headless_display.hpp>
+
+#include <mbgl/platform/log.hpp>
+
+// #include <cassert>
+
+#include <GL/glx.h>
+
+namespace mbgl {
+
+gl::glProc HeadlessBackend::initializeExtension(const char* name) {
+    return glXGetProcAddress(reinterpret_cast<const GLubyte*>(name));
+}
+
+void HeadlessBackend::createContext() {
+    xDisplay = display->xDisplay;
+    fbConfigs = display->fbConfigs;
+
+    if (!glContext) {
+        // Try to create a legacy context
+        glContext = glXCreateNewContext(xDisplay, fbConfigs[0], GLX_RGBA_TYPE, None, True);
+        if (glContext) {
+            if (!glXIsDirect(xDisplay, glContext)) {
+                Log::Error(Event::OpenGL, "failed to create direct OpenGL Legacy context");
+                glXDestroyContext(xDisplay, glContext);
+                glContext = nullptr;
+            }
+        }
+    }
+
+    if (glContext == nullptr) {
+        throw std::runtime_error("Error creating GL context object.");
+    }
+
+    // Create a dummy pbuffer. We will render to framebuffers anyway, but we need a pbuffer to
+    // activate the context.
+    int pbufferAttributes[] = {
+        GLX_PBUFFER_WIDTH, 8,
+        GLX_PBUFFER_HEIGHT, 8,
+        None
+    };
+    glxPbuffer = glXCreatePbuffer(xDisplay, fbConfigs[0], pbufferAttributes);
+}
+
+void HeadlessBackend::destroyContext() {
+    if (glxPbuffer) {
+        glXDestroyPbuffer(xDisplay, glxPbuffer);
+        glxPbuffer = 0;
+    }
+
+    glXDestroyContext(xDisplay, glContext);
+}
+
+void HeadlessBackend::activateContext() {
+    if (!glXMakeContextCurrent(xDisplay, glxPbuffer, glxPbuffer, glContext)) {
+        throw std::runtime_error("Switching OpenGL context failed.\n");
+    }
+}
+
+void HeadlessBackend::deactivateContext() {
+    if (!glXMakeContextCurrent(xDisplay, 0, 0, nullptr)) {
+        throw std::runtime_error("Removing OpenGL context failed.\n");
+    }
+}
+
+} // namespace mbgl