source/graphics/egl_android/glcontext.cpp

   1 #include <vector>
   2 #include <EGL/egl.h>
   3 #include <GLES2/gl2.h>
   4 #include <android/native_window.h>
   5 #include "display.h"
   6 #include "glcontext.h"
   7 #include "window_private.h"
   8
   9 using namespace std;
  10
  11 namespace Msp {
  12 namespace Graphics {
  13
  14 struct GLContext::Private
  15 {
  16         EGLDisplay display;
  17         EGLConfig config;
  18         EGLSurface surface;
  19         EGLContext context;
  20
  21         void attach(WindowHandle);
  22         void detach();
  23 };
  24
  25
  26 void GLContext::platform_init(const GLOptions &opts)
  27 {
  28         EGLDisplay egl_display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
  29         if(egl_display==EGL_NO_DISPLAY)
  30                 throw runtime_error("no egl display");
  31
  32         if(!eglInitialize(egl_display, 0, 0))
  33                 throw runtime_error("could not initialize egl");
  34
  35         vector<int> attribs;
  36
  37         attribs.push_back(EGL_COLOR_BUFFER_TYPE);
  38         attribs.push_back(EGL_RGB_BUFFER);
  39         attribs.push_back(EGL_RENDERABLE_TYPE);
  40         attribs.push_back(EGL_OPENGL_ES2_BIT);
  41         attribs.push_back(EGL_SURFACE_TYPE);
  42         attribs.push_back(EGL_WINDOW_BIT);
  43         attribs.push_back(EGL_DEPTH_SIZE);
  44         attribs.push_back(1);
  45
  46         if(opts.alpha)
  47         {
  48                 attribs.push_back(EGL_ALPHA_SIZE);
  49                 attribs.push_back(1);
  50         }
  51
  52         if(opts.stencil)
  53         {
  54                 attribs.push_back(EGL_STENCIL_SIZE);
  55                 attribs.push_back(1);
  56         }
  57
  58         if(opts.multisample>0)
  59         {
  60                 attribs.push_back(EGL_SAMPLE_BUFFERS);
  61                 attribs.push_back(1);
  62                 attribs.push_back(EGL_SAMPLES);
  63                 attribs.push_back(opts.multisample);
  64         }
  65
  66         attribs.push_back(EGL_NONE);
  67
  68         EGLConfig config;
  69         int num_configs;
  70         if(!eglChooseConfig(egl_display, &attribs.front(), &config, 1, &num_configs))
  71         {
  72                 eglTerminate(egl_display);
  73                 throw unsupported_gl_mode(opts);
  74         }
  75
  76         priv = new Private;
  77         priv->display = egl_display;
  78         priv->config = config;
  79
  80         /* Must wait for the window to be available, because the calling code
  81         expects GL to be usable after creation of the context. */
  82         WindowHandle native_window;
  83         const Window::Private &window_priv = window.get_private();
  84         while(!(native_window = window_priv.window))
  85                 display.tick();
  86
  87         int format;
  88         eglGetConfigAttrib(priv->display, config, EGL_NATIVE_VISUAL_ID, &format);
  89         ANativeWindow_setBuffersGeometry(native_window, 0, 0, format);
  90
  91         priv->surface = eglCreateWindowSurface(priv->display, config, native_window, 0);
  92
  93         eglBindAPI(EGL_OPENGL_ES_API);
  94         int context_attribs[] = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE };
  95         priv->context = eglCreateContext(priv->display, config, 0, context_attribs);
  96
  97         eglMakeCurrent(priv->display, priv->surface, priv->surface, priv->context);
  98
  99         window_priv.signal_window_acquired.connect(sigc::mem_fun(priv, &Private::attach));
 100         window_priv.signal_window_lost.connect(sigc::mem_fun(priv, &Private::detach));
 101 }
 102
 103 GLContext::~GLContext()
 104 {
 105         eglDestroyContext(priv->display, priv->context);
 106         if(priv->surface!=EGL_NO_SURFACE)
 107                 eglDestroySurface(priv->display, priv->surface);
 108         eglTerminate(priv->display);
 109         delete priv;
 110 }
 111
 112 void GLContext::swap_buffers()
 113 {
 114         eglSwapBuffers(priv->display, priv->surface);
 115 }
 116
 117 void GLContext::window_resized(unsigned, unsigned)
 118 { }
 119
 120
 121 void GLContext::Private::attach(WindowHandle native_window)
 122 {
 123         surface = eglCreateWindowSurface(display, config, native_window, 0);
 124         eglMakeCurrent(display, surface, surface, context);
 125 }
 126
 127 void GLContext::Private::detach()
 128 {
 129         eglMakeCurrent(display, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
 130         eglDestroySurface(display, surface);
 131 }
 132
 133 } // namespace Graphics
 134 } // namespace Msp