You will soon see that the actions you provide to a character can be quite a bit more complex than just blinking. In fact, the idea is that you tell the character what you want it to do at a highlevel, using actions such as Look, Point, and Say. Later in this tutorial we'll show how the Character API can create the frame array you saw in the code above, so that you don't have to.
Media Semantics Character Builder Key Code
The ability to stitch together different image strips as needed is sometimes referred to as "non-linear" media, and is key to allowing characters to react touser events, and present personalized information, such as a stock quote, or tomorrow's weather.
Images strips are coded using either the PNG or the JPEG format, as determined by the 'format' parameter on the Animate URL. Which you choose depends on a couple factors.PNG animation includes transparency, while JPEG does not. So if your application includes a character that appears over top of other content on your website, thenyou must use PNG. PNG tends to be very efficient for cartoon characters, because of the long runs of solid color. Being a lossless format, it will faithfully captureevery pixel.
On the other hand, JPEG is especially good at coding realistic or 3D characters. The JPEG format comes with a quality parameter - if not specified the value 75 is used.While the bandwidth can be reduced by lowering the quality, the result will be more artifacts, particularly when you do have a solid run of color. Furthermore, if you areswitching from one image strip to another with non-linear media, bear in mind that the switch from the last frame of one strip to the first frame of another stripmay result in a slight difference in these artifacts, as the JPEG algorithm uses different tradeoffs for different image strips. These differences tend to behard to notice in practice, in particular for higher compression quality factors.
Not every frame will have recovery information - generally if the character is mid-action, it will wait until the action is complete to recover.You can think of abort() as being a request to "hurry up" the animation. Note that the "recovery=true" option generally does not increase the size of theimage strips generated - it just adds a little more information that allows our client-side code to smoothly recover from an interruption.
One limitation of image strips is that you frequently have only one portion of an image that is animating. In our blink strip at the beginning of thistutorial, only a rectangular portion around the eyes change at any given time. A more efficient way to encode animation is to use texture maps.So far we have been using image strips only because they are easy to understand and work with. If you omit &strip=true then you get the default behavior,which is to create a larger rectangular image that packs many pieces of character imagery of different sizes. Such an image is often called a "sprite sheet", "texture map", or simply "texture".For example the result of running the action[say][lookleft]test[/say]looks like this:
One way to do this composition is to create an HTML5 Canvas the full size of your character, and use the drawImage javascript API to copy each layer from the source coordinates inthe texture map to the target coordinates in the canvas. To do this, you might use code such as the following:
If a request specifies the Content-Type header with the JSON:API media type,servers MUST respond with a 415 Unsupported Media Type status code ifthat media type contains any media type parameters other than ext orprofile.
If a request specifies the Content-Type header with an instance ofthe JSON:API media type modified by the ext media type parameter and thatparameter contains an unsupported extension URI, the server MUST respondwith a 415 Unsupported Media Type status code.
However, application/x-www-form-urlencoded parsing contains the bizarrehistorical artifact that + characters must be treated as spaces, and itrequires that all values be percent-decoded during parsing, which makes itimpossible to use RFC 3986 delimiter charactersas delimiters. These issues motivate the exception that JSON:API defines above.
Variable-length Unicode character string having maximum length size characters. You must specify size for NVARCHAR2. The number of bytes can be up to two times size for AL16UTF16 encoding and three times size for UTF8 encoding. Maximum size is determined by the national character set definition, with an upper limit of:
A character large object containing Unicode characters. Both fixed-width and variable-width character sets are supported, both using the database national character set. Maximum size is (4 gigabytes - 1) * (database block size). Stores national character set data.
When you create a table with a CHAR column, you specify the column length as size optionally followed by a length qualifier. The qualifier BYTE denotes byte length semantics while the qualifier CHAR denotes character length semantics. In the byte length semantics, size is the number of bytes to store in the column. In the character length semantics, size is the number of code points in the database character set to store in the column. A code point may have from 1 to 4 bytes depending on the database character set and the particular character encoded by the code point. Oracle recommends that you specify one of the length qualifiers to explicitly document the desired length semantics of the column. If you do not specify a qualifier, the value of the NLS_LENGTH_SEMANTICS parameter of the session creating the column defines the length semantics, unless the table belongs to the schema SYS, in which case the default semantics is BYTE.
Oracle ensures that all values stored in a CHAR column have the length specified by size in the selected length semantics. If you insert a value that is shorter than the column length, then Oracle blank-pads the value to column length. If you try to insert a value that is too long for the column, then Oracle returns an error. Note that if the column length is expressed in characters (code points), blank-padding does not guarantee that all column values have the same byte length.
The maximum value of size is 2000, which means 2000 bytes or characters (code points), depending on the selected length semantics. However, independently, the absolute maximum length of any character value that can be stored into a CHAR column is 2000 bytes. For example, even if you define the column length to be 2000 characters, Oracle returns an error if you try to insert a 2000-character value in which one or more code points are wider than 1 byte. The value of size in characters is a length constraint, not guaranteed capacity. If you want a CHAR column to be always able to store size characters in any database character set, use a value of size that is less than or equal to 500.
The NCHAR data type specifies a fixed-length character string in the national character set. You specify the national character set as either AL16UTF16 or UTF8 when you create your database. AL16UTF16 and UTF8 are two encoding forms of the Unicode character set (UTF-16 and CESU-8, correspondingly) and hence NCHAR is a Unicode-only data type.
When you create a table with an NCHAR column, you specify the column length as size characters, or more precisely, code points in the national character set. One code point has always 2 bytes in AL16UTF16 and from 1 to 3 bytes in UTF8, depending on the particular character encoded by the code point.
The maximum value of size is 1000 characters when the national character set is AL16UTF16, and 2000 characters when the national character set is UTF8. However, independently, the absolute maximum length of any character value that can be stored into an NCHAR column is 2000 bytes. For example, even if you define the column length to be 1000 characters, Oracle returns an error if you try to insert a 1000-character value but the national character set is UTF8 and all code points are 3 bytes wide. The value of size is a length constraint, not guaranteed capacity. If you want an NCHAR column to be always able to store size characters in both national character sets, use a value of size that is less than or equal to 666.
When you create a table with a VARCHAR2 column, you must specify the column length as size optionally followed by a length qualifier. The qualifier BYTE denotes byte length semantics while the qualifier CHAR denotes character length semantics. In the byte length semantics, size is the maximum number of bytes that can be stored in the column. In the character length semantics, size is the maximum number of code points in the database character set that can be stored in the column. A code point may have from 1 to 4 bytes depending on the database character set and the particular character encoded by the code point. Oracle recommends that you specify one of the length qualifiers to explicitly document the desired length semantics of the column. If you do not specify a qualifier, the value of the NLS_LENGTH_SEMANTICS parameter of the session creating the column defines the length semantics, unless the table belongs to the schema SYS, in which case the default semantics is BYTE.
While size may be expressed in bytes or characters (code points) the independent absolute maximum length of any character value that can be stored into a VARCHAR2 column is 32767 or 4000 bytes, depending on MAX_STRING_SIZE. For example, even if you define the column length to be 32767 characters, Oracle returns an error if you try to insert a 32767-character value in which one or more code points are wider than 1 byte. The value of size in characters is a length constraint, not guaranteed capacity. If you want a VARCHAR2 column to be always able to store size characters in any database character set, use a value of size that is less than or equal to 8191, if MAX_STRING_SIZE = EXTENDED, or 1000, if MAX_STRING_SIZE = STANDARD.
Do not use the VARCHAR data type. Use the VARCHAR2 data type instead. Although the VARCHAR data type is currently synonymous with VARCHAR2, the VARCHAR data type is scheduled to be redefined as a separate data type used for variable-length character strings compared with different comparison semantics. 2ff7e9595c
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