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#include <mbgl/platform/default/headless_backend.hpp>
#include <mbgl/platform/default/headless_display.hpp>
#include <mbgl/platform/log.hpp>
#include <EGL/egl.h>
#include <cassert>
namespace mbgl {
struct EGLImpl : public HeadlessBackend::Impl {
EGLImpl(EGLContext glContext_, EGLDisplay display_)
: glContext(glContext_),
display(display_) {
}
~EGLImpl() {
if (glContext != eglGetCurrentContext()) {
activateContext();
}
if (!eglDestroyContext(display, glContext)) {
throw std::runtime_error("Failed to destroy EGL context.\n");
}
}
void activateContext() final {
if (!eglMakeCurrent(display, EGL_NO_SURFACE, EGL_NO_SURFACE, glContext)) {
throw std::runtime_error("Switching OpenGL context failed.\n");
}
}
void deactivateContext() final {
if (!eglMakeCurrent(display, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT)) {
throw std::runtime_error("Removing OpenGL context failed.\n");
}
}
EGLContext glContext = EGL_NO_CONTEXT;
EGLDisplay display = EGL_NO_DISPLAY;
};
gl::glProc HeadlessBackend::initializeExtension(const char* name) {
return eglGetProcAddress(name);
}
bool HeadlessBackend::hasDisplay() {
if (!display) {
display.reset(new HeadlessDisplay);
}
return bool(display);
};
void HeadlessBackend::createContext() {
assert(!hasContext());
assert(hasDisplay());
EGLDisplay display_ = display->attribute<EGLDisplay>();
EGLConfig& config = display->attribute<EGLConfig&>();
// EGL initializes the context client version to 1 by default. We want to
// use OpenGL ES 2.0 which has the ability to create shader and program
// objects and also to write vertex and fragment shaders in the OpenGL ES
// Shading Language.
const EGLint attribs[] = {
EGL_CONTEXT_CLIENT_VERSION, 2,
EGL_NONE
};
EGLContext glContext = eglCreateContext(display_, config, EGL_NO_CONTEXT, attribs);
if (glContext == EGL_NO_CONTEXT) {
mbgl::Log::Error(mbgl::Event::OpenGL, "eglCreateContext() returned error 0x%04x",
eglGetError());
throw std::runtime_error("Error creating the EGL context object.\n");
}
impl.reset(new EGLImpl(glContext, display_));
}
} // namespace mbgl
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