Texturing system

Abstract

A texturing system for use in a three-dimensional graphics system has an input for receiving object data for an object to be textured. Encrypted texture data is obtained from a store a decrypted in a decryption unit. The decrypted texture data generates texture image data for a frame buffer from where it can be output for display. There is also provides a method for producing a software application for use in a three-dimensional graphics system which creates instructions for a software application and creates static texture data for use in conjunction with the instructions. The static texture data is encrypted and provided as encrypted texture data with the software instructions, A protected software application can be distributed to a target device from a distribution device by coupling the distribution device to the target device, transferring target device identifier data from the target device to the distribution device and using the target device identifier data in the distribution device to generate encryption definition data specific to the target device. The protected software application and encryption definition data are then transferred to the target device.

1 . A texturing system for use in a three-dimensional graphics system, the texturing system comprising: 
 an input for receiving object data describing an object to be textured;    a store for storing encrypted texture data for applying to an object to be textured;    a decryption unit, coupled to the store, for decrypting the encrypted texture data;    a framebuffer, coupled to the input and to the decryption unit, for applying decrypted texture data to object data to generate textured image data; and    an output, coupled to the framebuffer, for outputting textured image data for display.    
     
     
         2 . A texturing system according to  claim 1 , wherein the input is configured to receive encryption key identification data identifying the encryption key used to encrypt the texture data, the texturing system further comprising a key production unit, coupled to decryption unit and to the input, for generating the encryption key from the encryption key identification data, whereby the decryption unit uses the encryption key to decrypt the encrypted texture data.  
     
     
         3 . A texturing system according to either  claim 1  or  claim 2 , wherein: 
 the store is configured to store encrypted texture and checksum data;  
 the decryption unit is configured to decrypt the encrypted texture and checksum data and separate the data into texture data and checksum data;  
 and the system further comprises a protection unit, coupled to the decryption unit, for monitoring the checksum data and for adapting the output of the texturing system if the checksum data does not match control checksum data.  
 
     
     
         4 . A method of applying texturing to three-dimensional graphics data, the method comprising the steps of: 
 storing encrypted texture data for applying to texture an object;    receiving object data describing an object to be textured using stored texture data;    accessing and decrypting the encrypted texture data;    applying the decrypted texture data to the object data to generate textured image data; and    outputting the textured image data for display.    
     
     
         5 . A method according to  claim 4 , further comprising the steps of: 
 receiving encryption key identification data identifying the encryption key used to encrypt the texture data;    calculating the encryption key from the encryption key identification data; and    using the encryption key to decrypt the encrypted texture data.    
     
     
         6 . A method of producing a software application for use in a three-dimensional graphics system, the method comprising the steps of: 
 (a) creating instructions for a software application;    (b) creating static texture data to be used by a device in conjunction with the instructions to run the software application;    (c) encrypting the static texture data using an encryption algorithm; and    (d) outputting the encrypted texture data and software instructions as the software application.    
     
     
         7 . A method according to  claim 6 , comprising the additional steps of; 
 generating checksum data for the static texture data;    combining the checksum data and the static texture data;    and wherein step (c) is modified to encrypt the combined checksum and static texture data.    
     
     
         8 . A method according to  claim 1 , wherein the checksum data is generated from a first plurality of words selected from the beginning of the texture data.  
     
     
         9 . A method of distributing a protected software application from a distribution device to a target device, the method comprising the steps of: 
 coupling the distribution device to the target device;    transferring target device identifier data from from the target device to the distribution device;    using the target device identifier data in the distribution device to generate encryption definition data specific to the target device;    transferring the protected software application and the encryption definition data from the distribution device to the target device for subsequent use by the target device to enable the protected software application to be run,    
     
     
         10 . A method according to  claim 9 , wherein the encryption definition data is itself encrypted to form a Sales Key and wherein the Sales Key is transferred with the protected software application to the target device.  
     
     
         11 . A 3-d graphics device for running software applications comprising instructions and encrypted texture data, the device comprising: 
 a CPU for running a software application;    a memory, coupled to the CPU, for storing a software application;    a display for displaying 3-d graphics generated by running a software application; and    a texturing system according to any of  claims 1  to  3 , the input of the texturing system being coupled to the CPU and the output being coupled to the display.    
     
     
         12 . A 3-d graphics device according to  claim 11 , wherein the texturing system is configured to store a device identifier for use by a distribution device.  
     
     
         13 . A distribution device for distributing a protected software application to a target device, the distribution device comprising: 
 a receiver for receiving target identifier data from a target device;    a combiner, coupled to the receiver, for generating encryption definition data from the target identifier data and an application encryption key; and    an output for outputting a protected software application and the encryption definition data to a target device for use by the target device to enable the protected software application to be run.    
     
     
         14 . A distribution device according to  claim 13 , further comprising: 
 an encrypter, coupled to the combiner and to the output, for encrypting the encryption definition data to form a Sales Key, wherein the output outputs the Sales Key and the software application to a target device for use by the target device to enable the protected software application to be run.    
     
     
         15 . Apparatus substantially as hereinbefore described with reference to any of FIGS.  2  to  7 .  
     
     
         16 . A method substantially as hereinbefore described with reference to any of FIGS.  2  to  7 .