Add multiview to the opengl3 driver

4 files changed, 73 insertions, 0 deletions

diff --git a/platform/web/SCsub b/platform/web/SCsub
index cb00fa9f5b..077024507a 100644
--- a/platform/web/SCsub
+++ b/platform/web/SCsub
@@ -35,6 +35,7 @@ sys_env.AddJSLibraries(
         "js/libs/library_godot_os.js",
         "js/libs/library_godot_runtime.js",
         "js/libs/library_godot_input.js",
+        "js/libs/library_godot_webgl2.js",
     ]
 )
 
diff --git a/platform/web/display_server_web.cpp b/platform/web/display_server_web.cpp
index f6a61b18e4..2ee1edd2b4 100644
--- a/platform/web/display_server_web.cpp
+++ b/platform/web/display_server_web.cpp
@@ -773,6 +773,9 @@ DisplayServerWeb::DisplayServerWeb(const String &p_rendering_driver, WindowMode
 		if (emscripten_webgl_make_context_current(webgl_ctx) != EMSCRIPTEN_RESULT_SUCCESS) {
 			webgl2_init_failed = true;
 		} else {
+			if (!emscripten_webgl_enable_extension(webgl_ctx, "OVR_multiview2")) {
+				// @todo Should we log this?
+			}
 			RasterizerGLES3::make_current();
 		}
 	}
diff --git a/platform/web/godot_webgl2.h b/platform/web/godot_webgl2.h
index 968b70f84b..ae6b23ae18 100644
--- a/platform/web/godot_webgl2.h
+++ b/platform/web/godot_webgl2.h
@@ -34,4 +34,21 @@
 #include "GLES3/gl3.h"
 #include "webgl/webgl2.h"
 
+#define GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_NUM_VIEWS_OVR 0x9630
+#define GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_BASE_VIEW_INDEX_OVR 0x9632
+#define GL_MAX_VIEWS_OVR 0x9631
+#define GL_FRAMEBUFFER_INCOMPLETE_VIEW_TARGETS_OVR 0x9633
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void godot_webgl2_glFramebufferTextureMultiviewOVR(GLenum target, GLenum attachment, GLuint texture, GLint level, GLint baseViewIndex, GLsizei numViews);
+
+#define glFramebufferTextureMultiviewOVR godot_webgl2_glFramebufferTextureMultiviewOVR
+
+#ifdef __cplusplus
+}
+#endif
+
 #endif // GODOT_WEBGL2_H
diff --git a/platform/web/js/libs/library_godot_webgl2.js b/platform/web/js/libs/library_godot_webgl2.js
new file mode 100644
index 0000000000..365f712be7
--- /dev/null
+++ b/platform/web/js/libs/library_godot_webgl2.js
@@ -0,0 +1,52 @@
+/*************************************************************************/
+/*  library_godot_webgl2.js                                               */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+const GodotWebGL2 = {
+	$GodotWebGL2__deps: ['$GL', '$GodotRuntime'],
+	$GodotWebGL2: {},
+
+	godot_webgl2_glFramebufferTextureMultiviewOVR__deps: ['emscripten_webgl_get_current_context'],
+	godot_webgl2_glFramebufferTextureMultiviewOVR__proxy: 'sync',
+	godot_webgl2_glFramebufferTextureMultiviewOVR__sig: 'viiiiii',
+	godot_webgl2_glFramebufferTextureMultiviewOVR: function (target, attachment, texture, level, base_view_index, num_views) {
+		const context = GL.currentContext;
+		if (typeof context.multiviewExt === 'undefined') {
+			const ext = context.GLctx.getExtension('OVR_multiview2');
+			if (!ext) {
+				console.error('Trying to call glFramebufferTextureMultiviewOVR() without the OVR_multiview2 extension');
+				return;
+			}
+			context.multiviewExt = ext;
+		}
+		context.multiviewExt.framebufferTextureMultiviewOVR(target, attachment, GL.textures[texture], level, base_view_index, num_views);
+	},
+};
+
+autoAddDeps(GodotWebGL2, '$GodotWebGL2');
+mergeInto(LibraryManager.library, GodotWebGL2);