Graph

The graph window allows to easily draw curves and other sets of data with different colors and shapes in a rectangular window. The graph doesn't take any user input.

Style

The graph window provides an interface to modify the appearance of the graph itself and the data it displays. This contains the following properties:

• Point
  • Type (None / Dot / Square / Circle)
  • Radius
  • Color
• Lines
  • Type (None / Solid / Dot / Dash)
  • Thickness
  • Color
• X-Axis line
  • Type (Solid / Dot / Dash)
  • Thickness
  • Color
• Y-Axis
  • Type (Solid / Dot / Dash)
  • Thickness
  • Color
• X-Axis grid
  • Type (Solid / Dot / Dash)
  • Thickness
  • Color
  • Spacing
• Y-Axis grid
  • Type (Solid / Dot / Dash)
  • Thickness
  • Color
  • Spacing
• Flags
  • Arrows

API reference

The API reference of the graph window can be found here.

Example

The following example creates three curves with different colors and shapes within the same graph widget. Make sure you got the math library included into your build path (-lm).

#include "gfx.h"
#include "math.h"
 
static const point data[5] = {
    { -40, -40 },
    { 70, 40 },
    { 140, 60 },
    { 210, 60 },
    { 280, 200 }
};
 
static GGraphObject g;
 
static GGraphStyle GraphStyle1 = {
    { GGRAPH_POINT_DOT, 0, Blue },          // point
    { GGRAPH_LINE_NONE, 2, Gray },          // line
    { GGRAPH_LINE_SOLID, 0, White },        // x axis
    { GGRAPH_LINE_SOLID, 0, White },        // y axis
    { GGRAPH_LINE_DASH, 5, Gray, 50 },      // x grid
    { GGRAPH_LINE_DOT, 7, Yellow, 50 },     // y grid
    GWIN_GRAPH_STYLE_POSITIVE_AXIS_ARROWS   // flags
};
 
static const GGraphStyle GraphStyle2 = {
    { GGRAPH_POINT_SQUARE, 5, Red },        // point
    { GGRAPH_LINE_DOT, 2, Pink },           // line
    { GGRAPH_LINE_SOLID, 0, White },        // x axis
    { GGRAPH_LINE_SOLID, 0, White },        // y axis
    { GGRAPH_LINE_DASH, 5, Gray, 50 },      // x grid
    { GGRAPH_LINE_DOT, 7, Yellow, 50 },     // y grid
    GWIN_GRAPH_STYLE_POSITIVE_AXIS_ARROWS   // flags
};
 
int main(void) {
    GHandle     gh;
    uint16_t    i;
 
    gfxInit();
 
    {
        GWindowInit wi;
 
        wi.show = TRUE;
        wi.x = wi.y = 0;
        wi.width = gdispGetWidth();
        wi.height = gdispGetHeight();
        gh = gwinGraphCreate(&g, &wi);
    }
 
    gwinGraphSetOrigin(gh, gwinGetWidth(gh)/2, gwinGetHeight(gh)/2);
    gwinGraphSetStyle(gh, &GraphStyle1);
    gwinGraphDrawAxis(gh);
 
    for(i = 0; i < gwinGetWidth(gh); i++)
        gwinGraphDrawPoint(gh, i-gwinGetWidth(gh)/2, 80*sin(2*0.2*M_PI*i/180));
 
    gwinGraphStartSet(gh);
    GraphStyle1.point.color = Green;
    gwinGraphSetStyle(gh, &GraphStyle1);
 
    for(i = 0; i < gwinGetWidth(gh)*5; i++)
        gwinGraphDrawPoint(gh, i/5-gwinGetWidth(gh)/2, 95*sin(2*0.2*M_PI*i/180));
 
    gwinGraphStartSet(gh);
    gwinGraphSetStyle(gh, &GraphStyle2);
 
    gwinGraphDrawPoints(gh, data, sizeof(data)/sizeof(data[0]));
 
    while(TRUE) {
        gfxSleepMilliseconds(100);
    }
}