1.2.1 Data Types and Variables


Contents

ANSI C Data Types

Origin C supports all the ANSI C data types: char, short, int, float, double and void. In addition, you can have an array of, and a pointer to, each of these data types. 

char name[50];       // Declare an array of characters
unsigned char age;   // Declare an unsigned 8-bit integer
unsigned short year; // Declare an unsigned 16-bit integer

Origin C Composite Data Types

Although the C syntax for declaring an array is supported, Origin C provides string, vector and matrix classes to simplify working with data types in one or two dimensional arrays. These data types include char, byte, short, word, int, uint, complex. A vector can be of type string for a string array, but a matrix cannot. A matrix can be of numerical types only. 

string str = "hello, world\n";        // Declare and initialize a string

vector<double> vA1 = {1.5, 1.8, 1.1}; // Declare and initialize doubles
vector vA2 = {2.5, 2.8, 2.1, 2.4};    

vector<string> vs(3);                 // Declare a string array
vs[0] = "This ";                      // Assign string to each string array item
vs[1] = "is ";
vs[2] = "test";                                    

matrix<int> mA1;                      // Declare a matrix of integers
matrix mA2;                           // Declare a matrix of doubles

// NOTE: The double data type is implied when a data type is not
// specified in the declaration of vector and matrix variables.

Another useful class provided by Origin C is the complex class. The complex class supports numeric data containing both a real and an imaginary component. 

complex cc(4.5, 7.8);        // Declare a complex value.
                             // The real component is set to 4.5 and
                             // the imaginary component is set to 7.8
out_complex("value = ", cc); // Output the complex value

Color

Colors in Origin C are represented with a DWORD value. These values can be an index into Origin's internal color palette or an actual color composed of red, green, and blue components.

Palette Index

Origin's internal Palette contains 24 colors. An index into Origin's internal color palette is a zero based value from 0 to 23. Origin C provides named constants for each of these colors. Each name begins with the prefix SYSCOLOR_ followed by the name of the color. The following table lists the 24 color names and their indices.

Index Name Index Name
0 SYSCOLOR_BLACK 12 SYSCOLOR_DKCYAN
1 SYSCOLOR_RED 13 SYSCOLOR_ROYAL
2 SYSCOLOR_GREEN 14 SYSCOLOR_ORANGE
3 SYSCOLOR_BLUE 15 SYSCOLOR_VIOLET
4 SYSCOLOR_CYAN 16 SYSCOLOR_PINK
5 SYSCOLOR_MAGENTA 17 SYSCOLOR_WHITE
6 SYSCOLOR_YELLOW 18 SYSCOLOR_LTGRAY
7 SYSCOLOR_DKYELLOW 19 SYSCOLOR_GRAY
8 SYSCOLOR_NAVY 20 SYSCOLOR_LTYELLOW
9 SYSCOLOR_PURPLE 21 SYSCOLOR_LTCYAN
10 SYSCOLOR_WINE 22 SYSCOLOR_LTMAGENTA
11 SYSCOLOR_OLIVE 23 SYSCOLOR_DKGRAY 


DWORD dwColor = SYSCOLOR_ORANGE;

Auto Color

There is a special color index referred to as Auto. When this index is used the element will be colored using the same color as its parent. Not all elements support the Auto index. See Origin's graphical user interface for the element to determine if the Auto index is supported.

The INDEX_COLOR_AUTOMATIC macro is used when the Auto index value is needed. 

DWORD dwColor = INDEX_COLOR_AUTOMATIC;

RGB

An Origin color value can also represent an RGB value. RGB values are made up of 8-bit red, green, and blue components. These values can easily be made using the RGB macro}. 

DWORD brown = RGB(139,69,19); // saddle brown

The values returned from the RGB macro cannot be directly used as Origin color values. You will need to use the RGB2OCOLOR macro to convert the RGB values to Origin color values. 

DWORD brown = RGB2OCOLOR(RGB(139,69,19)); // saddle brown

If you ever need to know whether an Origin color value represents an RGB value or an index into a palette then you can use the OCOLOR_IS_RGB macro. This macro returns true if the value represents an RGB value and returns false otherwise. 

if( OCOLOR_IS_RGB(ocolor) )
    out_str("color value represents an RGB color");
else
    out_str("color value represents a color index");

Once you determine that an Origin color value represents an RGB value, then you can use the GET_CRF_FROM_RGBOCOLOR macro to extract the RGB value from the Origin color value. 

if( OCOLOR_IS_RGB(ocolor) )
{
    DWORD rgb = GET_CRF_FROM_RGBOCOLOR(ocolor);
    printf("red = %d, green = %d, blue = %d\n",
        GetRValue(rgb), GetGValue(rgb), GetBValue(rgb));
}