Names over the heads at 60% of their size on the HUD

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

port/android/host/host_xr.c

@@ -794,6 +794,12 @@ the eyes reads it. Shown only while it is. */
 
 #define WRIST_IMAGE_SIZE 512
 #define CROSSHAIR_IMAGE_SIZE 256
+/* the names layer: HALO_XR_MAXIMUM_NAMES slots of 4:1, one over another */
+#define NAMES_IMAGE_WIDTH 512
+#define NAMES_IMAGE_HEIGHT (NAMES_IMAGE_WIDTH / 4 * HALO_XR_MAXIMUM_NAMES)
+/* a name's slot, as the game draws it: wider than its image's 4:1 (the
+game's 640x480 drawn square): the height a slot shows at, to its width */
+#define NAME_SLOT_ASPECT (30.0f / 160.0f)
 #define WRIST_BEHIND_PALM 0.05f
 #define WRIST_DOWN_HANDLE 0.02f
 #define WRIST_ABOVE_HAND 0.04f
@@ -1032,8 +1038,15 @@ int host_xr_initialize(struct halo_xr_info *info, float wanted_refresh_rate)
 	{
 		int size = layer == HALO_XR_LAYER_WRIST || layer == HALO_XR_LAYER_SCOPE ? WRIST_IMAGE_SIZE :
 			layer == HALO_XR_LAYER_CROSSHAIR ? CROSSHAIR_IMAGE_SIZE : 0;
+		int width = size ? size : xr.eye_width;
+		int height = size ? size : xr.eye_height;
 
-		if (!swapchain_create(&xr.swapchains[layer], size ? size : xr.eye_width, size ? size : xr.eye_height))
+		if (layer == HALO_XR_LAYER_NAMES)
+		{
+			width = NAMES_IMAGE_WIDTH;
+			height = NAMES_IMAGE_HEIGHT;
+		}
+		if (!swapchain_create(&xr.swapchains[layer], width, height))
 			return 0;
 	}
 	if (!copy_initialize() || !actions_initialize())
@@ -1354,7 +1367,8 @@ int host_xr_end_frame(const struct halo_xr_submit *submit)
 	XrCompositionLayerQuad wrist = { XR_TYPE_COMPOSITION_LAYER_QUAD };
 	XrCompositionLayerQuad scope = { XR_TYPE_COMPOSITION_LAYER_QUAD };
 	XrCompositionLayerQuad crosshair = { XR_TYPE_COMPOSITION_LAYER_QUAD };
-	const XrCompositionLayerBaseHeader *layers[5];
+	XrCompositionLayerQuad names[HALO_XR_MAXIMUM_NAMES];
+	const XrCompositionLayerBaseHeader *layers[5 + HALO_XR_MAXIMUM_NAMES];
 	uint32_t layer_count = 0;
 	int eye;
 
@@ -1458,6 +1472,34 @@ int host_xr_end_frame(const struct halo_xr_submit *submit)
 		layers[layer_count++] = (const XrCompositionLayerBaseHeader *)&crosshair;
 	}
 
+	if (xr.frame_state.shouldRender && submit->name_count > 0 && xr.swapchains[HALO_XR_LAYER_NAMES].filled)
+	{
+		struct xr_swapchain *swapchain = &xr.swapchains[HALO_XR_LAYER_NAMES];
+		int slot_height = swapchain->height / HALO_XR_MAXIMUM_NAMES;
+		int name;
+
+		for (name = 0; name < submit->name_count && name < HALO_XR_MAXIMUM_NAMES; name++)
+		{
+			XrCompositionLayerQuad *quad_name = &names[name];
+
+			memset(quad_name, 0, sizeof(*quad_name));
+			quad_name->type = XR_TYPE_COMPOSITION_LAYER_QUAD;
+			quad_name->layerFlags = XR_COMPOSITION_LAYER_BLEND_TEXTURE_SOURCE_ALPHA_BIT;
+			quad_name->space = xr.local_space;
+			quad_name->eyeVisibility = XR_EYE_VISIBILITY_BOTH;
+			quad_name->subImage.swapchain = swapchain->handle;
+			/* (slot 0 at the image's top: GL's rows run bottom up) */
+			quad_name->subImage.imageRect.offset.x = 0;
+			quad_name->subImage.imageRect.offset.y = swapchain->height - (name + 1) * slot_height;
+			quad_name->subImage.imageRect.extent.width = swapchain->width;
+			quad_name->subImage.imageRect.extent.height = slot_height;
+			quad_name->size.width = submit->name_widths[name];
+			quad_name->size.height = submit->name_widths[name] * NAME_SLOT_ASPECT;
+			pose_to_xr(&quad_name->pose, &submit->name_poses[name]);
+			layers[layer_count++] = (const XrCompositionLayerBaseHeader *)quad_name;
+		}
+	}
+
 	end.displayTime = xr.frame_state.predictedDisplayTime;
 	end.environmentBlendMode = XR_ENVIRONMENT_BLEND_MODE_OPAQUE;
 	end.layerCount = layer_count;

port/android/include/halo_xr_abi.h

@@ -27,7 +27,10 @@ enum
 	HALO_XR_LAYER_WRIST = 3,   /* the motion tracker, on the left wrist */
 	HALO_XR_LAYER_SCOPE = 4,   /* the zoomed view, a disc over the weapon */
 	HALO_XR_LAYER_CROSSHAIR = 5, /* the weapon's crosshair, where it aims */
-	HALO_XR_LAYER_COUNT = 6,
+	HALO_XR_LAYER_NAMES = 6,   /* players' names, each a quad over a head */
+	HALO_XR_LAYER_COUNT = 7,
+	/* the names layer's slots, one a name, stacked from its top */
+	HALO_XR_MAXIMUM_NAMES = 8,
 
 	/* host_xr_copy_layer's clear_alpha: the source's alpha kept, made
 	opaque, or cut to a disc (premultiplied) */
@@ -147,6 +150,12 @@ struct halo_xr_submit
 	int crosshair;
 	float crosshair_size;
 	struct halo_xr_pose crosshair_pose;
+	/* the names layer was filled: its first name_count slots, each shown
+	this wide (metres, a slot's height following from its shape), here in
+	LOCAL space, facing the eyes */
+	int name_count;
+	float name_widths[HALO_XR_MAXIMUM_NAMES];
+	struct halo_xr_pose name_poses[HALO_XR_MAXIMUM_NAMES];
 };
 
 #endif

port/linux/include/halo_vr.h

@@ -140,6 +140,15 @@ out (halo_vr_scope_pass). */
 int halo_vr_scope(short local_player_index, float magnification, float position[3], float forward[3], float up[3],
 	float *vertical_field_of_view);
 int halo_vr_scope_pass(void);
+/* Players' names over their heads (hud.c, render.c): whether they are drawn
+apart this frame; the slot a name is drawn into (left, top, right, bottom
+of the game's 640x480); a name's place (world units, over the head),
+giving its slot (-1: no more); and the slots, drawn on the cleared back
+buffer, taken (it is cleared again) */
+int halo_vr_names_apart(void);
+void halo_vr_name_slot(int slot, short bounds[4]);
+int halo_vr_add_name(const float point[3]);
+void halo_vr_capture_names(void);
 /* how much higher than a rifle's the weapon in hand has its scope's disc
 (metres; render.c, before halo_vr_scope) */
 void halo_vr_set_scope_raise(float metres);

port/linux/src/vr.c

@@ -134,6 +134,11 @@ static struct
 	float scope_size;
 	int crosshair;
 	int crosshair_captured;  /* this frame (halo_vr_capture_crosshair) */
+	/* players' names this frame (halo_vr_add_name), and whether their
+	slots were taken (halo_vr_capture_names) */
+	int name_count;
+	float name_points[HALO_XR_MAXIMUM_NAMES][3];
+	int names_captured;
 	/* the barrel of the weapon as drawn (halo_vr_set_barrel): where shots,
 	the crosshair and the laser start */
 	float barrel[3];
@@ -242,6 +247,7 @@ the target), keeping the size it has in the HUD: this part of the HUD. */
 static void cross3(const float a[3], const float b[3], float out[3]);
 static float normalize3(float v[3]);
 static int crosshair_pose(struct halo_xr_pose *pose, float *size);
+static int name_pose(const float point[3], struct halo_xr_pose *pose, float *width);
 static int weapon_hand_tracked(short local_player_index);
 static void controller_axes(float forward[3], float up[3], float right[3]);
 static void hand_offset(float out[3]);
@@ -1021,6 +1027,8 @@ void halo_vr_frame_begin(void)
 	vr.eyes_captured = 0;
 	vr.scope_captured = 0;
 	vr.crosshair_captured = 0;
+	vr.name_count = 0;
+	vr.names_captured = 0;
 	vr.overlay_mode = HALO_XR_OVERLAY_SCREEN;
 	vr.overlay_blend = 0;
 	if (vr.frame.recentred)
@@ -1087,6 +1095,20 @@ void halo_vr_present(unsigned int back_buffer_texture)
 	weapon aims */
 	if (vr.crosshair_captured && vr.overlay_mode == HALO_XR_OVERLAY_HEAD_LOCKED)
 		submit.crosshair = crosshair_pose(&submit.crosshair_pose, &submit.crosshair_size);
+	/* the names, each over its player's head */
+	if (vr.names_captured && submit.eyes && vr.overlay_mode == HALO_XR_OVERLAY_HEAD_LOCKED)
+	{
+		int name;
+
+		for (name = 0; name < vr.name_count; name++)
+		{
+			if (name_pose(vr.name_points[name], &submit.name_poses[submit.name_count],
+				&submit.name_widths[submit.name_count]))
+			{
+				submit.name_count++;
+			}
+		}
+	}
 	if (vr.scope_captured && submit.eyes)
 	{
 		submit.scope = 1;
@@ -1947,6 +1969,82 @@ static int crosshair_pose(struct halo_xr_pose *pose, float *size)
 	return 1;
 }
 
+/* ---------- players' names
+
+Names over the heads (hud.c) are drawn into slots of a region of the back
+buffer, one under another, before the HUD, and each slot is shown on a quad
+of its own over its player's head, facing the eyes, as wide as the name
+looks at the HUD's distance: in VR the HUD is a screen at one distance,
+where names drawn on it hung before the eyes. */
+
+#define NAME_SLOT_LEFT 240
+#define NAME_SLOT_WIDTH 160
+#define NAME_SLOT_HEIGHT 30
+/* how large a name looks against the HUD's text (smaller: over a head, not
+on the screen before the eyes) */
+#define NAME_SCALE 0.6f
+
+int halo_vr_names_apart(void)
+{
+	return vr.active && halo_vr_stereo_frame();
+}
+
+void halo_vr_name_slot(int slot, short bounds[4])
+{
+	bounds[0] = NAME_SLOT_LEFT;
+	bounds[1] = (short)(slot * NAME_SLOT_HEIGHT);
+	bounds[2] = NAME_SLOT_LEFT + NAME_SLOT_WIDTH;
+	bounds[3] = (short)((slot + 1) * NAME_SLOT_HEIGHT);
+}
+
+int halo_vr_add_name(const float point[3])
+{
+	int slot = vr.name_count;
+
+	if (slot >= HALO_XR_MAXIMUM_NAMES)
+		return -1;
+	memcpy(vr.name_points[slot], point, sizeof(vr.name_points[slot]));
+	vr.name_count++;
+	return slot;
+}
+
+void halo_vr_capture_names(void)
+{
+	if (vr.name_count > 0)
+	{
+		vr.names_captured = host_xr_copy_layer_region(HALO_XR_LAYER_NAMES, d3d8_back_buffer_texture(),
+			HALO_XR_COPY_ALPHA, NAME_SLOT_LEFT / 640.0f, 0.0f, (NAME_SLOT_LEFT + NAME_SLOT_WIDTH) / 640.0f,
+			HALO_XR_MAXIMUM_NAMES * NAME_SLOT_HEIGHT / 480.0f);
+	}
+	d3d8_clear_back_buffer(0.0f, 0.0f, 0.0f, 0.0f);
+}
+
+static int name_pose(const float point[3], struct halo_xr_pose *pose, float *width)
+{
+	static const float world_up[3] = { 0.0f, 1.0f, 0.0f };
+	float x[3], y[3], z[3];
+	float distance;
+	float angle;
+	int axis;
+
+	world_to_local(point, pose->position);
+	for (axis = 0; axis < 3; axis++)
+		z[axis] = vr.frame.head.position[axis] - pose->position[axis];
+	distance = normalize3(z);
+	/* (facing the eyes, upright) */
+	if (distance < 0.05f)
+		return 0;
+	cross3(world_up, z, x);
+	if (normalize3(x) < 1e-4f)
+		return 0;
+	cross3(z, x, y);
+	quaternion_from_axes(x, y, z, pose->orientation);
+	/* (as wide as the slot looks on the HUD, smaller) */
+	angle = (float)NAME_SLOT_WIDTH / 640.0f * vr.hud_width / vr.hud_distance * NAME_SCALE;
+	*width = 2.0f * distance * tanf(angle * 0.5f);
+	return 1;
+}
+
 /* ---------- the scope
 
 Zoomed in, the weapon shows its view on a disc over the barrel, like a
@@ -2175,6 +2273,10 @@ int halo_vr_scope(short local_player_index, float magnification, float position[
 	return 0;
 }
 int halo_vr_scope_pass(void) { return 0; }
+int halo_vr_names_apart(void) { return 0; }
+void halo_vr_name_slot(int slot, short bounds[4]) { (void)slot; (void)bounds; }
+int halo_vr_add_name(const float point[3]) { (void)point; return -1; }
+void halo_vr_capture_names(void) {}
 void halo_vr_set_scope_raise(float metres) { (void)metres; }
 void halo_vr_capture_scope(float left, float top, float right, float bottom)
 {

source/interface/hud.c

@@ -1033,13 +1033,6 @@ static short hud_player_names_setting(
 		}
 	}
 
-#ifdef HALO_ANDROID
-	/* (the VR port's: in VR the HUD is a screen at a fixed distance before
-	the eyes, so names drawn on it hang there, not over the heads; none
-	until they are drawn into each eye's picture) */
-	if (halo_vr_active())
-		return _player_names_none;
-#endif
 	return setting;
 }
 
@@ -1134,7 +1127,8 @@ static void hud_draw_player_name(
 	long player_index,
 	boolean ally,
 	boolean indicator,
-	real enemy_range)
+	real enemy_range,
+	boolean vr_apart)
 {
 	struct player_datum const *player = player_get(player_index);
 	long font_index = hud_get_font_index();
@@ -1164,10 +1158,35 @@ static void hud_draw_player_name(
 	/* (where the game draws a teammate's triangle) */
 	head_position.z += 0.30000001f;
 	matrix4x3_transform_point(&render.frustum.world_to_view, &head_position, &view_position);
-	if (!render_camera_view_to_screen(&render.camera, &render.frustum, &view_position, &screen_position))
-		return;
-	x = (short)fast_ftol(screen_position.x) - render.camera.viewport_bounds.x0;
-	y = (short)fast_ftol(screen_position.y) - render.camera.viewport_bounds.y0;
+#ifdef HALO_ANDROID
+	if (vr_apart)
+	{
+		/* (VR: in a slot of its own, shown over the head: halo_vr.h) */
+		float point[3];
+		short slot_bounds[4];
+		int slot;
+
+		point[0] = head_position.x;
+		point[1] = head_position.y;
+		point[2] = head_position.z + (indicator ? 0.15f : 0.0f);
+		slot = halo_vr_add_name(point);
+		if (slot < 0)
+			return;
+		halo_vr_name_slot(slot, slot_bounds);
+		x = (short)((slot_bounds[0] + slot_bounds[2]) / 2);
+		y = (short)(slot_bounds[3] - 4);
+		/* (an ally's whole at any distance it is drawn at) */
+		view_position.z = -1.0f;
+		indicator = FALSE;
+	}
+	else
+#endif
+	{
+		if (!render_camera_view_to_screen(&render.camera, &render.frustum, &view_position, &screen_position))
+			return;
+		x = (short)fast_ftol(screen_position.x) - render.camera.viewport_bounds.x0;
+		y = (short)fast_ftol(screen_position.y) - render.camera.viewport_bounds.y0;
+	}
 	if (indicator)
 	{
 		struct bitmap_data *bitmap = bitmap_group_get_bitmap_from_sequence(
@@ -1209,8 +1228,32 @@ static void hud_draw_player_name(
 	return;
 }
 
+static void hud_draw_player_names_now(
+	boolean vr_apart);
+
 static void hud_draw_player_names(
 	void)
+{
+#ifdef HALO_ANDROID
+	/* (VR: apart, before the HUD: hud_draw_player_names_vr) */
+	if (halo_vr_active())
+		return;
+#endif
+	hud_draw_player_names_now(FALSE);
+}
+
+#ifdef HALO_ANDROID
+/* VR: the names drawn into their slots, each then shown over its player's
+head (render.c, before the HUD; halo_vr_names_apart) */
+void hud_draw_player_names_vr(
+	void)
+{
+	hud_draw_player_names_now(TRUE);
+}
+#endif
+
+static void hud_draw_player_names_now(
+	boolean vr_apart)
 {
 	short setting = hud_player_names_setting();
 	long player_index = local_player_get_player_index(render.local_player_index);
@@ -1235,7 +1278,7 @@ static void hud_draw_player_names(
 			continue;
 		if ((ally && setting == _player_names_enemies) || (!ally && setting == _player_names_allies))
 			continue;
-		hud_draw_player_name(iterator.datum_index, ally, ally && indicators, enemy_range);
+		hud_draw_player_name(iterator.datum_index, ally, ally && indicators, enemy_range, vr_apart);
 	}
 
 	return;

source/interface/hud.h

@@ -29,6 +29,11 @@ struct hud_scripted_globals_definition
 /* ---------- prototypes/HUD.C */
 
 #ifdef HALO_ANDROID
+#ifdef HALO_ANDROID
+/* VR: players' names drawn into their slots (halo_vr_names_apart) */
+void hud_draw_player_names_vr(
+	void);
+#endif
 void hud_draw_crosshair(
 	void);
 #endif

source/render/render.c

@@ -853,6 +853,14 @@ static void render_vr_overlay(
 	parameters.suppress_clear = TRUE;
 	parameters.window_index = render.window_index;
 
+	if (!menus_active && halo_vr_names_apart())
+	{
+		/* the players' names, each to be shown over its head */
+		rasterizer_window_begin(&parameters);
+		hud_draw_player_names_vr();
+		rasterizer_window_end();
+		halo_vr_capture_names();
+	}
 	if (!menus_active && halo_vr_crosshair_apart())
 	{
 		/* the weapon's crosshair alone, taken to where the weapon aims */