From cba45b4d123b9843bddcdbc536d5502bba8e0305 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Thomas=20K=C3=B6ppe?= <tkoeppe@google.com>
Date: Thu, 18 Oct 2018 11:22:09 +0100
Subject: [PATCH] Headless renderer. Attempting something like in #76.

---
 BUILD                                       | 35 ++++++++-----
 engine/code/deepmind/headless_macos_glimp.c | 58 +++++++++++++++++++++
 2 files changed, 79 insertions(+), 14 deletions(-)
 create mode 100644 engine/code/deepmind/headless_macos_glimp.c

diff --git a/BUILD b/BUILD
index 8d6331243..91837e763 100644
--- a/BUILD
+++ b/BUILD
@@ -802,10 +802,26 @@ cc_library(
     hdrs = ["public/dmlab.h"],
     copts = IOQ3_COMMON_COPTS,
     defines = IOQ3_COMMON_DEFINES,
-    linkopts = [
-        "-lGL",
-        "-lrt",
+    linkopts = ["-framework OpenGL"],
+    deps = IOQ3_COMMON_DEPS,
+)
+
+cc_library(
+    name = "game_lib_headless_macos",
+    srcs = IOQ3_COMMON_SRCS + [
+        CODE_DIR + "/deepmind/dmlab_connect.c",
+        CODE_DIR + "/null/null_input.c",
+        CODE_DIR + "/null/null_snddma.c",
+
+        ## OpenGL rendering
+        CODE_DIR + "/deepmind/headless_macos_glimp.c",
+        CODE_DIR + "/deepmind/glimp_common.h",
+        CODE_DIR + "/deepmind/glimp_common.c",
     ],
+    hdrs = ["public/dmlab.h"],
+    copts = IOQ3_COMMON_COPTS,
+    defines = IOQ3_COMMON_DEFINES,
+    linkopts = ["-framework OpenGL"],
     deps = IOQ3_COMMON_DEPS,
 )
 
@@ -897,27 +913,18 @@ config_setting(
 
 cc_binary(
     name = "libdmlab_headless_hw.so",
-    linkopts = ["-Wl,--version-script,$(location :dmlab.lds)"],
     linkshared = 1,
     linkstatic = 1,
     visibility = ["//testing:__subpackages__"],
-    deps = [":dmlab.lds"] + select({
-        "dmlab_graphics_osmesa_or_egl": [":game_lib_headless_egl"],
-        "dmlab_graphics_osmesa_or_glx": [":game_lib_headless_glx"],
-        "//conditions:default": [":game_lib_headless_egl"],
-    }),
+    deps = [":game_lib_headless_macos"],
 )
 
 cc_binary(
     name = "libdmlab_headless_sw.so",
-    linkopts = ["-Wl,--version-script,$(location :dmlab.lds)"],
     linkshared = 1,
     linkstatic = 1,
     visibility = ["//testing:__subpackages__"],
-    deps = [
-        ":dmlab.lds",
-        ":game_lib_headless_osmesa",
-    ],
+    deps = [":game_lib_headless_osmesa"],
 )
 
 cc_library(
diff --git a/engine/code/deepmind/headless_macos_glimp.c b/engine/code/deepmind/headless_macos_glimp.c
new file mode 100644
index 000000000..659b704eb
--- /dev/null
+++ b/engine/code/deepmind/headless_macos_glimp.c
@@ -0,0 +1,58 @@
+#include <dlfcn.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <OpenGL/OpenGL.h>
+#include <OpenGL/gl3.h>
+
+#include "glimp_common.h"
+
+static CGLContextObj context;
+
+void GLimp_MakeCurrent(void) {
+}
+
+void GLimp_Init(void) {
+  CGLPixelFormatObj pix;
+  GLint npix;
+  int attribs[] = {
+    kCGLPFAAccelerated,     // no software rendering
+    kCGLPFAOpenGLProfile,
+    kCGLOGLPVersion_Legacy,
+    0
+  };
+
+  GLimp_CommonPreInit();
+
+  // NOTE: in headless mode there is no GUI, hence output to console instead of message boxes
+
+  if (CGLChoosePixelFormat((CGLPixelFormatAttribute*)attribs, &pix, &npix) != kCGLNoError) {
+    // Sys_Error("GLimp_Init - choose pixel format error!\n");
+    printf("GLimp_Init - choose pixel format error!\n");
+    exit(1);
+  }
+  if (CGLCreateContext(pix, NULL, &context) != kCGLNoError) {
+    // Sys_Error("GLimp_Init - create context error!\n");
+    printf("GLimp_Init - create context error!\n");
+    exit(1);
+  }
+  if (CGLSetCurrentContext(context) != kCGLNoError) {
+    // Sys_Error("GLimp_Init - set current context error!");
+    printf("GLimp_Init - set current context error!\n");
+    exit(1);
+  }
+  CGLDestroyPixelFormat(pix);
+
+  printf("Renderer: %s\nVersion: %s\n", glGetString(GL_RENDERER), glGetString(GL_VERSION));
+
+  GLimp_CommonPostInit();
+}
+
+void* GLimp_GetProcAddress(const char* func) {
+  return dlsym(RTLD_SELF, func);
+}
+
+void GLimp_Shutdown(void) {
+  CGLSetCurrentContext(NULL);
+  CGLDestroyContext(context);
+}