Shadow Generation Apparatus and Method

Abstract

Apparatus and a method for generating a shadow onto a real world surface is described, with the shadow being related to a virtual object in for example a game world. The apparatus (24) comprises a light source (26), receiving means (28) for receiving a real world description, and shadow generation control means (30) which control the light source to generate a shadow for projection onto the real world surface (18) in dependence on the received real world description. Hence, apparatus that delivers shadow effects in a room in order to enhance a gaming or movie watching experience is provided.

Description

This invention relates to apparatus and a method for providing real world visual cues to a user. In particular this invention relates to apparatus adapted to deliver shadow effects in a room to enhance a gaming experience. The invention has particular, but not exclusive, application to computer gaming and home theatre systems.

Patent application WO 02/092183 describes a real world representation system and language in which a set of devices are operated according to a received real world description and hence render the real world experience to the user. For example the devices may output visible color tones and luminance onto the walls of a private dwelling in dependence on the received description. The description may be embedded or provided with a broadcast signal thereby linking the description to audio/visual content within the broadcast. Hence an ambient immersive environment is created, which is flexible, scalable and provides an enhanced experience to a user.

Patent application WO 02/092182 in particular describes the application of the concepts described in WO 02/092183 in a gaming environment thereby rendering in the real world, in real time, effects related to the game world model displayed for example on a display. Effects such as lighting levels, (relative/absolute, moods, colors, position, focus) and mood—emotional, ambient, animated and so on are disclosed. In one example, the real-world description reads <FOREST>, <SUMMER>, <EVENING>, which is interpreted into specific instructions relating to the color tones and luminance level required, such as a color tone of a pleasant green and the light level low but warm. Hence, such an environment in the game world may be rendered in the real world providing an enhanced game playing experience.

It is also common to provide real time shadows for virtual objects in accordance with virtual lighting conditions within a virtual environment such as a displayed computer game, as described in EP0948978. Such shadows provide a visual cue as to the virtual position of the object in the virtual world to the game player. Such shadows also serve to reinforce the perceived “presence” of an object in a virtual world.

However, it may be that such visual cues may be useful in the real world, for example in circumstances where objects not within the game characters displayed field of view are present.

There is therefore a desire to provide apparatus and a method capable of providing real world shadow effects in a gaming or home theatre application.

According to a first aspect of the invention, there is provided apparatus for projecting a shadow related to a virtual object present in a virtual world, onto a real world surface, comprising a light source, receiving means for receiving a real world description, and shadow generation control means which control the light source to generate a shadow for projection onto the real world surface in dependence on the received real world description. According to a second aspect of the invention, there is provided a method for providing a real world shadow effect related to a virtual object, comprising receiving a real world description in the form of an instruction set of a markup language, and controlling a light source to generate a shadow in dependence on the received real world description.

Owing to the invention, it is possible to provide a real world shadow effect associated with for example a monster in a computer game, thereby providing an enhanced experience. For example, a monster located “behind” the game character in the game world, may cast a shadow onto the real wall in front or to the side of the user, thereby alerting the user controlling the game character that something nasty is “behind” him. Alternatively, an aeroplane flying overhead in a movie or game may cast a shadow onto the floor or across a wall in front of the user.

The game may have the real world description encoded within it to provide to the shadow apparatus, or a software engine or browser such as that described in WO 02/092182 may analyze the game world and objects therein and hence provide the real world description to the apparatus. Alternatively, a broadcast may provide the real world description in addition to the audio/video stream, or the video stream may be analyzed as described in WO 02/092182.

In one embodiment of the first aspect, the shadow effect is generated by apparatus comprising a small array of light emitting diodes with suitable lens for projection. Advantageously, only a relatively low resolution array is required since having a rather fuzzy, or indistinctly edged shadow adds to the experience since it is mostly the users peripheral vision that picks up the shadow. Hence a compact and relatively inexpensive peripheral may be provided to enhance a game playing or movie watching experience. In another embodiment of the first aspect, apparatus in the form of a liquid crystal display projector is provided with control means to generate a shadow effect in dependence on the real world description.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 is a schematic perspective view of a real world representation system including shadow generating apparatus,

FIG. 2 shows example set up views of the system,

FIG. 3 illustrates an embodiment of shadow generating apparatus in operation,

FIG. 4 illustrates another embodiment of shadow generating apparatus in operation, and

FIG. 5 illustrates a low resolution shadow moving from left to right.

FIG. 1 illustrates a real world representation system comprising a set of devices including a computer with display device 10, audio speakers 12, a lighting device 14, a heating device 16, walls 18, floor 20. These devices together contribute to make up the ambient environment, each device being arranged to provide one or more real-world parameters. For example, the lighting device 14 contributes color tones as well as to the luminance level. The devices may be electronic or they may be purely mechanical. The devices are interconnected by either a wireless network or a wired network such as a powerline carrier network. Of course the environment may include normal furniture 22. The computer may be a so-called “media-PC” enabling computing, gaming and audio/video home theatre applications.

At least one of the devices making up the real-world representation system is arranged to receive a real-world description in the form of an instruction set of a markup language, the devices being operated according to said description. In this example, this description augments a computer game that a user is playing on computer 10. As different environments are encountered by the user's character, a description generated by computer 10 is transmitted to the devices in the system. The devices then render this description onto the real world environment of FIG. 1.

For a full description of the aspects of operation of such a real world system and real world description language, the reader is directed to published patent applications WO 02/092183 and WO 02/092182.

The system also includes shadow generating apparatus 24 (shown in more detail in FIGS. 2, 3 and 4) which is real world markup language enabled, and hence serves to increase the functionality of the real-world representation system. A user would purchase the shadow generating apparatus 24 to improve their enjoyment of, for example, a game that includes a real world description in the form of an instruction set of a markup language. The shadow generating apparatus 24 is arranged to provide extra functionality to a game in response to the received instruction set.

FIGS. 2a and 2b illustrate by way of example two possible arrangements for the shadow generation apparatus 24 in the real world environment.

The apparatus 24 comprises a light source 26 and receiving means 28 for receiving a real-world description in the form of an instruction set of a markup language via the wired or wireless network mentioned above. The apparatus further comprises shadow generation control means 30 for controlling the apparatus to generate a shadow 34 for projection via light source 26 in response to a received instruction.

The apparatus 24 may comprise a liquid crystal based projector with control means 30 in the form of a computer program and processor with a software device driver. Alternatively, the apparatus 24 may comprise a relatively inexpensive light emitting diode array provided with suitable lenses and control means in the form of a processor and software device driver.

FIG. 2a illustrates apparatus 24 arranged behind the user who is playing a game on computer 10. In FIG. 2a the apparatus may be ceiling or wall mounted. Suppose an enemy or monster is creeping up to the user controlled game character in the gameworld of computer 10. The apparatus operates according to the following example method. It receives via 28 a real world description in the form of a mark-up language, for example <shadow> <middle>. Control means 30 controls light source 26 to prevent light output in middle region 34 therefore causing a shadow 34 to be displayed on the wall in front of the user, providing a peripheral visual cue in the form of a shadow to the user that something is directly behind the character in the game world.

Other instructions relating to the relative size and position of the shadow may be received thereby creating a dynamic shadow effect for the user. For example, a template of shadow shapes associated with the real world description may be utilized in the controlling of the light source to generate the shadow effect (see FIG. 5).

FIG. 2b illustrates the apparatus 24 positioned in front of the user whilst still projecting a shadow 34 onto the wall 18. Hence the apparatus may be relatively portable and may sit on a table or desk beside or behind the user, depending on the relative distances involved in the users ambient experience enabled environment.

FIG. 3 shows in more detail an embodiment of apparatus 24. The apparatus comprises a light source 26 comprising an individually addressable array of individually addressable light emitting diodes (LED), of which only four are shown for clarity in the Figure. Each LED 26a-d has a respective associated lens 40 for projection, such as a fresnel lens. Those skilled in the art will recognize that other standard optical elements and components may be utilized to achieve shadow projection over the required distances. Control means 30 receives instruction via means 28 (here shown as a wireless antenna by way of example) and causes some of the LEDs to be switched off, or at a low light intensity level, whilst others are switched on to emit light. Hence, as shown in the Figure, LED 26a and LED 26d are on and emitting light 42, whilst LED 26b and 26c are switched off creating a shadow 34 on wall 18.

Experiments have shown that since the shadow is in the peripheral vision of the user, the shadow does not need to be of high resolution. In fact, fuzzy or indistinct edges appear to add to the atmosphere, and in fact an indistinct shape may be used and is adequate for fast objects such as aeroplanes which zoom overhead in the game world. Hence simple shadow templates for game characters, monsters, and other objects may be provided leading to reduced computing and control complexity, whilst still adding significantly to the atmosphere and experience of the user.

Furthermore, the low resolution requirements enable a small and inexpensive LED array to be used, such as a 10—10 array up to say 100×100 LEDs for example. Hence reasonably inexpensive, and portable shadow generation apparatus may be obtained.

FIG. 4 illustrates apparatus 24 in which a liquid crystal display (LCD) projector supplied with control means 30 is utilized. In this embodiment the liquid crystal display 44 comprises many pixels of which only five are shown schematically in the Figure for clarity. Control means 30 drives the display so that some pixels 44a, 44b emit light whilst some pixels 44c, 44d, 44e block light causing a shadow region 34 on wall 18.

The control means 30 in this embodiment may be provided within the apparatus 24, and may be in the form of a computer program and software device driver which receives the real world description, interprets it and controls the data written onto the LCD for output. Alternatively the computer 10 may directly drive the LCD for output. Hence, more complex geometric shadow shapes may be displayed by such apparatus, although as mentioned previously such shadows need not be sharp with detailed edges for the immersion effect to operate.

The description of the real-world experiences including shadow information relating to a virtual object in a game or video world is provided by a markup language that communicates a description of physical environments and the objects within them, their relationship to the user, each other and to the physical space. Within a location that is enabled to produce a real-world experience, the instruction set of the markup language is interpreted by a device or devices to render the experience.

For example, FIG. 5 illustrates a moving projected low resolution shadow 34 on the wall 18 representing perhaps a monster in the game world. Parts a, b and c of the Figure illustrate how the shadow may appear to move from left (a) to the middle (b) to the right (c) edge of the wall in response to the received real world description. The tiles in each part of the Figure represents the output of an LED for example, or of an area of a liquid crystal display and hence illustrates how a low resolution shadow may be generated and yet still appear convincing.

As mentioned previously, a template of such shadows may be provided either within the device or loaded into computer 10, thereby keeping processing and computing requirements to a reasonable level in contrast with the real time generation of game world shadows appreciated by those skilled in the art.

Whilst the invention has been described above in relation to projecting a shadow onto a real world surface, those skilled in the art will appreciate that a display enabled real world surface (for example a wall screen or a wall with a large display built into it) may also be controlled to generate and display a shadow, although this embodiment has a disadvantage in that the positioning of the computer 10 will be dictated by the non-portable fixed real world display surface for shadow effects.

Claims

1. Apparatus for projecting a shadow related to a virtual object, onto a real world surface, comprising a light source,

receiving means for receiving a real world description, and

shadow generation control means which control the light source to generate a shadow for projection onto the real world surface in dependence on the received real world description.

2. Apparatus as claimed in claim 1, wherein the light source comprises a plurality of addressable light emitting diodes, each of which outputs through a respective lens for projection.

3. Apparatus as claimed in claim 2, wherein each respective lens is a fresnel lens.

4. Apparatus as claimed in claim 2, wherein the shadow generation control means selectively addresses each light emitting diode in dependence on the received real world description to generate the shadow for projection.

5. Apparatus according to claim 1, wherein the apparatus comprises a liquid crystal display projector.

6. Apparatus according to claim 5, wherein the shadow generation control means selectively addresses the pixels of the display to generate the shadow for projection.

7. Apparatus according to claim 1, wherein the received real world description is in the form of an instruction set of a markup language.

8. Apparatus according to claim 1, wherein the received real world description includes location information.

9. Apparatus according to claim 1, wherein said real world surface comprises display means.

10. A method for providing a real world shadow effect related to a virtual object, comprising receiving a real world description in the form of an instruction set of a markup language, and controlling a light source to generate a shadow in dependence on the received real world description.

11. A method according to claim 10, wherein a template of shadow shapes associated with the real world description is used in said controlling of the light source to generate said shadow effect.