Add multiview to the opengl3 driver

6 files changed, 111 insertions, 29 deletions

diff --git a/drivers/gles3/storage/config.cpp b/drivers/gles3/storage/config.cpp
index 242c1ce0a9..609ecacded 100644
--- a/drivers/gles3/storage/config.cpp
+++ b/drivers/gles3/storage/config.cpp
@@ -34,6 +34,15 @@
 #include "core/config/project_settings.h"
 #include "core/templates/vector.h"
 
+#ifdef ANDROID_ENABLED
+#include <GLES3/gl3.h>
+#include <GLES3/gl3ext.h>
+#include <GLES3/gl3platform.h>
+
+#include <EGL/egl.h>
+#include <EGL/eglext.h>
+#endif
+
 using namespace GLES3;
 
 #define _GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT 0x84FF
@@ -98,6 +107,16 @@ Config::Config() {
 		anisotropic_level = MIN(float(1 << int(ProjectSettings::get_singleton()->get("rendering/textures/default_filters/anisotropic_filtering_level"))), anisotropic_level);
 	}
 
+	multiview_supported = extensions.has("GL_OVR_multiview2") || extensions.has("GL_OVR_multiview");
+#ifdef ANDROID_ENABLED
+	if (multiview_supported) {
+		eglFramebufferTextureMultiviewOVR = (PFNGLFRAMEBUFFERTEXTUREMULTIVIEWOVRPROC)eglGetProcAddress("glFramebufferTextureMultiviewOVR");
+		if (eglFramebufferTextureMultiviewOVR == nullptr) {
+			multiview_supported = false;
+		}
+	}
+#endif
+
 	force_vertex_shading = false; //GLOBAL_GET("rendering/quality/shading/force_vertex_shading");
 	use_nearest_mip_filter = GLOBAL_GET("rendering/textures/default_filters/use_nearest_mipmap_filter");
 
diff --git a/drivers/gles3/storage/config.h b/drivers/gles3/storage/config.h
index fe18345775..de08385e04 100644
--- a/drivers/gles3/storage/config.h
+++ b/drivers/gles3/storage/config.h
@@ -44,6 +44,10 @@
 #include OPENGL_INCLUDE_H
 #endif
 
+#ifdef ANDROID_ENABLED
+typedef void (*PFNGLFRAMEBUFFERTEXTUREMULTIVIEWOVRPROC)(GLenum, GLenum, GLuint, GLint, GLint, GLsizei);
+#endif
+
 namespace GLES3 {
 
 class Config {
@@ -82,6 +86,11 @@ public:
 	bool support_anisotropic_filter = false;
 	float anisotropic_level = 0.0f;
 
+	bool multiview_supported = false;
+#ifdef ANDROID_ENABLED
+	PFNGLFRAMEBUFFERTEXTUREMULTIVIEWOVRPROC eglFramebufferTextureMultiviewOVR = nullptr;
+#endif
+
 	static Config *get_singleton() { return singleton; };
 
 	Config();
diff --git a/drivers/gles3/storage/render_scene_buffers_gles3.cpp b/drivers/gles3/storage/render_scene_buffers_gles3.cpp
index 9123984dc7..b8e4530f56 100644
--- a/drivers/gles3/storage/render_scene_buffers_gles3.cpp
+++ b/drivers/gles3/storage/render_scene_buffers_gles3.cpp
@@ -33,12 +33,17 @@
 #include "render_scene_buffers_gles3.h"
 #include "texture_storage.h"
 
+#ifdef ANDROID_ENABLED
+#define glFramebufferTextureMultiviewOVR GLES3::Config::get_singleton()->eglFramebufferTextureMultiviewOVR
+#endif
+
 RenderSceneBuffersGLES3::~RenderSceneBuffersGLES3() {
 	free_render_buffer_data();
 }
 
 void RenderSceneBuffersGLES3::configure(RID p_render_target, const Size2i p_internal_size, const Size2i p_target_size, float p_fsr_sharpness, float p_texture_mipmap_bias, RS::ViewportMSAA p_msaa, RenderingServer::ViewportScreenSpaceAA p_screen_space_aa, bool p_use_taa, bool p_use_debanding, uint32_t p_view_count) {
 	GLES3::TextureStorage *texture_storage = GLES3::TextureStorage::get_singleton();
+	GLES3::Config *config = GLES3::Config::get_singleton();
 
 	//internal_size.x = p_internal_size.x; // ignore for now
 	//internal_size.y = p_internal_size.y;
@@ -50,7 +55,7 @@ void RenderSceneBuffersGLES3::configure(RID p_render_target, const Size2i p_inte
 	//msaa = p_msaa;
 	//screen_space_aa = p_screen_space_aa;
 	//use_debanding = p_use_debanding;
-	//view_count = p_view_count;
+	view_count = p_view_count;
 
 	free_render_buffer_data();
 
@@ -62,24 +67,43 @@ void RenderSceneBuffersGLES3::configure(RID p_render_target, const Size2i p_inte
 	glGenFramebuffers(1, &framebuffer);
 	glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
 
-	glBindTexture(GL_TEXTURE_2D, rt->color);
-	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, rt->color, 0);
+	if (view_count > 1 && config->multiview_supported) {
+		glBindTexture(GL_TEXTURE_2D_ARRAY, rt->color);
+		glFramebufferTextureMultiviewOVR(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, rt->color, 0, 0, view_count);
+	} else {
+		glBindTexture(GL_TEXTURE_2D, rt->color);
+		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, rt->color, 0);
+	}
 
 	glGenTextures(1, &depth_texture);
-	glBindTexture(GL_TEXTURE_2D, depth_texture);
-
-	glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT24, rt->size.x, rt->size.y, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, nullptr);
-
-	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
-	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+	if (view_count > 1 && config->multiview_supported) {
+		glBindTexture(GL_TEXTURE_2D_ARRAY, depth_texture);
+		glTexImage3D(GL_TEXTURE_2D_ARRAY, 0, GL_DEPTH_COMPONENT24, rt->size.x, rt->size.y, view_count, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, nullptr);
+
+		glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+		glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+		glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+		glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+	} else {
+		glBindTexture(GL_TEXTURE_2D, depth_texture);
+		glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT24, rt->size.x, rt->size.y, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, nullptr);
+
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+	}
 
-	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depth_texture, 0);
+	if (view_count > 1 && config->multiview_supported) {
+		glFramebufferTextureMultiviewOVR(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, depth_texture, 0, 0, view_count);
+	} else {
+		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depth_texture, 0);
+	}
 
 	GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
 
 	glBindTexture(GL_TEXTURE_2D, 0);
+	glBindTexture(GL_TEXTURE_2D_ARRAY, 0);
 	glBindFramebuffer(GL_FRAMEBUFFER, texture_storage->system_fbo);
 
 	if (status != GL_FRAMEBUFFER_COMPLETE) {
diff --git a/drivers/gles3/storage/render_scene_buffers_gles3.h b/drivers/gles3/storage/render_scene_buffers_gles3.h
index ad0d2032b0..dbedbd22c3 100644
--- a/drivers/gles3/storage/render_scene_buffers_gles3.h
+++ b/drivers/gles3/storage/render_scene_buffers_gles3.h
@@ -56,7 +56,7 @@ public:
 	RS::ViewportMSAA msaa = RS::VIEWPORT_MSAA_DISABLED;
 	//RS::ViewportScreenSpaceAA screen_space_aa = RS::VIEWPORT_SCREEN_SPACE_AA_DISABLED;
 	//bool use_debanding = false;
-	//uint32_t view_count = 1;
+	uint32_t view_count = 1;
 
 	bool is_transparent = false;
 
diff --git a/drivers/gles3/storage/texture_storage.cpp b/drivers/gles3/storage/texture_storage.cpp
index 554b4165fa..524ff14cc9 100644
--- a/drivers/gles3/storage/texture_storage.cpp
+++ b/drivers/gles3/storage/texture_storage.cpp
@@ -34,6 +34,10 @@
 #include "config.h"
 #include "drivers/gles3/effects/copy_effects.h"
 
+#ifdef ANDROID_ENABLED
+#define glFramebufferTextureMultiviewOVR GLES3::Config::get_singleton()->eglFramebufferTextureMultiviewOVR
+#endif
+
 using namespace GLES3;
 
 TextureStorage *TextureStorage::singleton = nullptr;
@@ -720,8 +724,7 @@ void TextureStorage::texture_proxy_initialize(RID p_texture, RID p_base) {
 }
 
 void TextureStorage::texture_2d_update(RID p_texture, const Ref<Image> &p_image, int p_layer) {
-	// only 1 layer so far
-	texture_set_data(p_texture, p_image);
+	texture_set_data(p_texture, p_image, p_layer);
 #ifdef TOOLS_ENABLED
 	Texture *tex = texture_owner.get_or_null(p_texture);
 
@@ -1012,7 +1015,7 @@ void TextureStorage::texture_set_data(RID p_texture, const Ref<Image> &p_image,
 		img->resize_to_po2(false);
 	}
 
-	GLenum blit_target = (texture->target == GL_TEXTURE_CUBE_MAP) ? _cube_side_enum[p_layer] : GL_TEXTURE_2D;
+	GLenum blit_target = (texture->target == GL_TEXTURE_CUBE_MAP) ? _cube_side_enum[p_layer] : texture->target;
 
 	Vector<uint8_t> read = img->get_data();
 
@@ -1069,7 +1072,11 @@ void TextureStorage::texture_set_data(RID p_texture, const Ref<Image> &p_image,
 			glCompressedTexImage2D(blit_target, i, internal_format, bw, bh, 0, size, &read[ofs]);
 		} else {
 			glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-			glTexImage2D(blit_target, i, internal_format, w, h, 0, format, type, &read[ofs]);
+			if (texture->target == GL_TEXTURE_2D_ARRAY) {
+				glTexSubImage3D(GL_TEXTURE_2D_ARRAY, i, 0, 0, p_layer, w, h, 0, format, type, &read[ofs]);
+			} else {
+				glTexImage2D(blit_target, i, internal_format, w, h, 0, format, type, &read[ofs]);
+			}
 		}
 
 		tsize += size;
@@ -1425,6 +1432,8 @@ void TextureStorage::_update_render_target(RenderTarget *rt) {
 		return;
 	}
 
+	Config *config = Config::get_singleton();
+
 	rt->color_internal_format = rt->is_transparent ? GL_RGBA8 : GL_RGB10_A2;
 	rt->color_format = GL_RGBA;
 	rt->color_type = rt->is_transparent ? GL_UNSIGNED_BYTE : GL_UNSIGNED_INT_2_10_10_10_REV;
@@ -1446,17 +1455,29 @@ void TextureStorage::_update_render_target(RenderTarget *rt) {
 
 		// color
 		glGenTextures(1, &rt->color);
-		glBindTexture(GL_TEXTURE_2D, rt->color);
-
-		glTexImage2D(GL_TEXTURE_2D, 0, rt->color_internal_format, rt->size.x, rt->size.y, 0, rt->color_format, rt->color_type, nullptr);
-
-		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+		if (rt->view_count > 1 && config->multiview_supported) {
+			glBindTexture(GL_TEXTURE_2D_ARRAY, rt->color);
+			glTexImage3D(GL_TEXTURE_2D_ARRAY, 0, rt->color_internal_format, rt->size.x, rt->size.y, rt->view_count, 0, rt->color_format, rt->color_type, nullptr);
+
+			glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+			glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+			glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+			glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+		} else {
+			glBindTexture(GL_TEXTURE_2D, rt->color);
+			glTexImage2D(GL_TEXTURE_2D, 0, rt->color_internal_format, rt->size.x, rt->size.y, 0, rt->color_format, rt->color_type, nullptr);
 
-		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
-		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+		}
 
-		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, rt->color, 0);
+		if (rt->view_count > 1 && config->multiview_supported) {
+			glFramebufferTextureMultiviewOVR(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, rt->color, 0, 0, rt->view_count);
+		} else {
+			glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, rt->color, 0);
+		}
 
 		GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
 
@@ -1475,8 +1496,15 @@ void TextureStorage::_update_render_target(RenderTarget *rt) {
 
 		texture->format = rt->image_format;
 		texture->real_format = rt->image_format;
-		texture->type = Texture::TYPE_2D;
-		texture->target = GL_TEXTURE_2D;
+		if (rt->view_count > 1 && config->multiview_supported) {
+			texture->type = Texture::TYPE_LAYERED;
+			texture->target = GL_TEXTURE_2D_ARRAY;
+			texture->layers = rt->view_count;
+		} else {
+			texture->type = Texture::TYPE_2D;
+			texture->target = GL_TEXTURE_2D;
+			texture->layers = 1;
+		}
 		texture->gl_format_cache = rt->color_format;
 		texture->gl_type_cache = GL_UNSIGNED_BYTE;
 		texture->gl_internal_format_cache = rt->color_internal_format;
@@ -1619,13 +1647,14 @@ void TextureStorage::render_target_set_size(RID p_render_target, int p_width, in
 	RenderTarget *rt = render_target_owner.get_or_null(p_render_target);
 	ERR_FAIL_COND(!rt);
 
-	if (p_width == rt->size.x && p_height == rt->size.y) {
+	if (p_width == rt->size.x && p_height == rt->size.y && p_view_count == rt->view_count) {
 		return;
 	}
 
 	_clear_render_target(rt);
 
 	rt->size = Size2i(p_width, p_height);
+	rt->view_count = p_view_count;
 
 	_update_render_target(rt);
 }
diff --git a/drivers/gles3/storage/texture_storage.h b/drivers/gles3/storage/texture_storage.h
index 39a74236e5..dbe39428ac 100644
--- a/drivers/gles3/storage/texture_storage.h
+++ b/drivers/gles3/storage/texture_storage.h
@@ -324,6 +324,7 @@ private:
 struct RenderTarget {
 	Point2i position = Point2i(0, 0);
 	Size2i size = Size2i(0, 0);
+	uint32_t view_count = 1;
 	int mipmap_count = 1;
 	RID self;
 	GLuint fbo = 0;