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--------------------------------------- RECORD# <lf#>, <record#> [,<char#>] The RECORD# command is used with an OPENed RELative disk file to position the record pointer to a particular record. The record pointer must be set to point to a particular record before any reading from or writing to that record can be accomplished (use GET#, INPUT#, or INPUT$() to read; PRINT# to write). <Lf#> is the logical file number used when the file was OPENed. <Record#> may range from 1 to 65535, although if zero is used Commodore DOS will automatically promote it to a 1. If RECORD# sets the record pointer to a record beyond the current last record in the file DOS error "50,RECORD NOT PRESENT,XX,XX" occurs. This is a fatal error if trying to read that record, but writing to a record beyond the current last record in a relative file causes that record and all intervening records to be created. This enables a relative file to be expanded whenever necessary (record creation is a time-consuming process for the disk drive, however, and it is often preferable to create large numbers of records a few times rather than small numbers of records many times). <Char#> is used to set the character pointer to a particular character within the record. Reading and writing takes place at the current position of the character pointer, with the pointer advancing one character each time a character is read or written. <Char#> may range from 1 to 254, although if zero is used Commodore DOS will automatically promote it to a 1. If <char#> is not specified it is assumed to be 1. If <char#> is larger than the record size DOS error "51,OVERFLOW IN RECORD,XX,XX" will occur. Examples: 10 RECORD# 3, 63 20 RECORD# 13, 650, 20 30 RECORD# 5, A: A$=INPUT$(100, #5) --------------------------------------- RESTORE [<line#>] The V2 Basic RESTORE statement has been modified to accept an optional line number. If <line#> is present RESTORE sets the internal data pointer to that line number. RESTORE with no line number sets the pointer to the first line of the program. READing continues normally starting with the first DATA statement on or after the line the data pointer points to. Examples: 10 RESTORE 20 RESTORE 1000 --------------------------------------- RUN [<line#>] The V2 Basic RUN command has been modified to set default screen scaling and sizing for bitmap graphics operations before beginning program execution. There is no other change in its behavior. Examples: RUN RUN 100 --------------------------------------- SAVE <filename$> [,<dvc#>] [,<addr>] The V2 Basic SAVE command has been modified to save <filename$> on the current default device if <dvc#> is not specified. There is no other change in its behavior. Examples: 10 SAVE "MYPROGRAM" 20 SAVE "THISPROGRAM",8 30 SAVE "THATPROGRAM",1,2 --------------------------------------- SCALE [<xrange/orient>] [,<yrange/orient>] [,<xorigin>] [,<yorigin>] SCALE sets the logical coordinate system of the bitmap screen. ERASE, LINE, LOCATE, POINT, and SPRLOC are all affected by logical scaling. CUR(), DRAW, and WRITE are not affected by logical scaling, except that they perform their functions starting at the current logical cursor position. The physical coordinate system of the bitmap screen consists of 64000 pixels arranged in 320 columns by 200 rows. The origin (coordinates 0,0) is at the upper left corner of the screen. X values increase from left to right, and Y values increase from top to bottom. The bottom right corner of the screen has coordinates 319,199. EVS Basic overlays the physical coordinate system with a logical coordinate system. Statements which accept logical coordinates automatically transform them into physical coordinates before use according to the equations: physical xpos = 320/<xrange/orient> * (<logical xpos> + <xorigin>) physical ypos = 200/<yrange/orient> * (<logical ypos> + (yorigin>) Logical coordinates which are outside the physical coordinate system after transformation are not legal, except in the case of the SPRLOC statement. The default logical screen coordinate system is equivalent to the physical coordinate system (which is the same as SCALE 320,200,0,0). RUNning a program resets the default logical coordinate system. SCALE without parameters resets the default logical coordinate system. If parameters are present it is not possible to "skip over" unused SCALE parameters. All must be present up to the last one actually used. Parameters not specified retain their current values. The range of all four parameters is -32768 to +32767, except that <xrange/orient> and <yrange/orient> may not be zero. The logical origin may be located anywhere, including outside the physical coordinate system. Examples: 10 SCALE 20 SCALE 320,-200,0,-199 30 SCALE 320,-240,160,-120 40 SCALE 280,192 50 SCALE 640,400 60 SCALE 2*3.14,-2,3.14,-1 --------------------------------------- SPRCOL <sprite# [,<sum>]>, <color> The SPRCOL statement sets the color of one or more sprites. For multicolor sprites, SPRCOL sets the color independent of the two shared multicolors. The VIC-II chip can display eight sprites, which EVS Basic numbers 1 to 8. Any single sprite can be affected by using its number for <sprite#>. In this case <sum> is not used and should not be present. Multiple sprites can be affected at the same time by using 0 for <sprite#> together with <sum>. <Sum> is calculated by starting with zero and adding 1 for sprite 1, 2 for sprite 2, 4 for sprite 3, 8 for sprite 4, 16 for sprite 5, 32 for sprite 6, 64 for sprite 7, and 128 for sprite 8. <Sum> has a maximum value of 255, which would affect all 8 sprites at once (1+2+4+8+16+32+64+128). <Color> may range from 0 to 15. Examples: 10 SPRCOL 1, 7 20 SPRCOL I, C(I) 30 SPRCOL 0, 255, 1 --------------------------------------- SPRITE <sprite# [,<sum>]>, [<enable> [,<priority> [,<xsize> [,<ysize> [,<multi>]]]]] SPRITE controls all the "on-or-off" aspects of the appearance of one or more sprites. The most important of these is visibility, but display priority, size, and multicolor mode are also included. <Sprite# [,<sum>]> has the same form and behavior as described for the SPRCOL statement. The remaining parameters are all expressions. If the expression is non-zero (true), the parameter will be turned "on". If the expression has a value of zero (false), the parameter will be turned "off". Parameters not present remain in their current state. <Enable> controls sprite visibility. An "off" sprite cannot be seen. If a sprite is "on" it may be visible (if it is located within the physical screen coordinates, if it has a color different from the paper color, if it is not hidden by foreground or another sprite). <Priority> controls what happens when a sprite and a foreground object appear in the same place on the screen. If "off" (higher), a sprite will appear in front of any foreground objects it crosses. If "on" (lower), the sprite will disappear behind them (sprites also have a built-in priority to other sprites. Sprite 1 has the highest, sprite 2 the second highest and so on down to sprite 8, which has the lowest priority. When two sprites cross the one with higher priority passes in front of the one with lower priority.). <Xsize> and <ysize> control horizontal and vertical sprite size. "Off" is normal size and "on" is double size. <Multi> controls sprite multicolor. A normal ("off") sprite can display only one color, while a multicolor ("on") sprite can also display either or both of the two additional colors shared by all multicolor sprites. The pixels of multicolor sprites are twice as wide and half as many as the pixels of normal sprites. SPRITE functions in all graphic modes except mode 0. Values set by a SPRITE statement remain in effect until changed by another SPRITE statement, with the exception that the GRAPHIC statement sets <enable> to "off" for all eight sprites. Examples: 10 SPRITE 1,1,0,0,0,1 20 SPRITE 3,,,X<312, Y<100 30 SPRITE 0,255,0 --------------------------------------- SPRLOC <sprite# [,<sum>]>, <xpos>, <ypos> SPRLOC positions one or more sprites on the logical screen. <Sprite# [,<sum>]> has the same form and behavior as described for the SPRLOC statement. <Xpos>, <ypos> sets the position of the upper left corner of a sprite. The range of <xpos>, <ypos> depends on the current logical screen coordinates. The default range is -24, -50 to 487, 205. Not all of these values correspond to locations on the physical screen. SPRLOC is the only statement that allows <xpos>, <ypos> to be outside the physical screen area. Normal-sized sprites are completely on the physical screen only within the range 0, 0 to 295, 178, and will be completely off the screen outside the range -23, -20 to 319, 199. SPRLOC functions in all graphic modes except mode 0. Examples: 10 SPRLOC 1, 160, 100 20 SPRLOC 0, 3, -24, -50 30 SPRLOC A, X(A), Y(A) -------------------------------------- SPRMULTI [<color1> [,<color2>]] The SPRMULTI statements sets the two colors shared by multicolor sprites. These colors are in addition to the unique color each sprite may have (which is set by SPRCOL). Like the multicolor graphic modes, in exchange for the two extra colors a multicolor sprite loses half its horizontal resolution as the pixels that make it up become twice as wide and half as many. Each color may range from 0 to 15. SPRMULTI functions in all graphic modes. Examples: 10 SPRMULTI 4, 0 20 SPRMULTI A 30 SPRMULTI ,A+1 --------------------------------------- SPRPIC <sprite# [,<sum>]>, <image> SPRPIC assigns a sprite image block to a sprite. A sprite "looks like" the image in the sprite image block currently assigned to it. <Sprite# [,<sum>]> has the same form and behavior described for the SPRLOC statement. Sprite image block numbers range from 0 to 206 (these are the same image blocks that are used by the IMAGE statement. The IMAGE statement is one way of assigning an image to a sprite image block). An image block itself has no default value. It is the programmer's responsibility to ensure that any image block used in a SPRPIC statement actually contains a useful image and causes no memory use conflict (see IMAGE for more details). The image block assigned to a sprite may be changed at any time (this is one way to animate a sprite). There are no default image block assignments to sprites. Examples: 10 SPRPIC 1, 8 20 SPRPIC 0, 3, P(A) --------------------------------------- SWAP <var1>, <var2> The SWAP statement exchanges the values of two variables. <Var1> and <var2> can be any two variables of the same type (real, integer, or string). It is not possible to SWAP a real with an integer variable (to exchange these two types it is necessary to use a third "holding" variable to temporarily store one of the two variables). Examples: 10 SWAP A, B 20 SWAP A$(I), A$(J) 30 SWAP A%, A%(I)