/// <summary>
/// Initializes a new instance of the <see cref="Axis"/> class
/// mostly with default values.
/// </summary>
/// <param name="TextInstance">The text instance.</param>
public Axis(TextInstance TextInstance)
{
_majorTic = new MajorTic();
_minorTic = new MinorTic();
_zoomCorrection = Default.zoomCorrection;
_zoomDiff = Default.zoomDiff;
_axisGap = Default.AxisGap;
_numSpace = Default.numSpace;
_scale = new Scale(this, TextInstance);
_textInstance = TextInstance;
}
/// <summary>
/// Draws the major tics. First their Number and their
/// Positions are calculated, then they are given to the
/// VBO as vertices to then be drawn.
/// </summary>
/// <param name="nTics">The n tics.</param>
/// <param name="pane">The pane.</param>
/// <param name="chart">The chart.</param>
internal void DrawMajorTics(int nTics, GraphPane pane, Chart chart)
{
double dVal;
float pixVal;
MajorTic tic = _ownerAxis._majorTic;
int firstTic = (int)(_min / _majorStep + 0.99);
int k = 0;
_ticsArray = new Vector2[2 * nTics + 2];
for (int i = firstTic; i < nTics + firstTic; i++)
{
dVal = _majorStep * i;
// If we're before the start of the scale, just go to the next tic
if (dVal < _min)
{
continue;
}
// if we've already past the end of the scale, then we're done
if (dVal > _max)
{
break;
}
pixVal = LocalTransform(dVal);
if (this._ownerAxis is XAxis)//Add two x/y-tupels to the array, one above, one below the axis
{
_ticsArray[k].X = -2 * pixVal / chart.Rect.Width + 1;
_ticsArray[k + 1].X = -2 * pixVal / chart.Rect.Width + 1;
_ticsArray[k].Y = -1;
_ticsArray[k + 1].Y = 1;
}
else if (this._ownerAxis is YAxis)
{
_ticsArray[k].X = -1;
_ticsArray[k + 1].X = 1;
_ticsArray[k].Y = -2 * pixVal / chart.Rect.Height + 1;
_ticsArray[k + 1].Y = -2 * pixVal / chart.Rect.Height + 1;
}
DrawTicValue(pane, chart, this._ownerAxis, pixVal, dVal);//at the position of every majorTic, draw a number
k += 2;
}
if (this._ownerAxis is XAxis)
{//the Viewports are directly put over the axis, so the _ticsArray has numbers rangig from -1 to 1 int one direction, just fitting the rectangle
GL.Viewport((int)chart.Rect.X, (int)(chart.Rect.Y - tic.Size), (int)chart.Rect.Width, (int)(2 * tic.Size));
}
else if (this._ownerAxis is YAxis)
{
GL.Viewport((int)(chart.Rect.X - tic.Size - _ownerAxis._fixedSpace * (this._ownerAxis as YAxis).Index), (int)chart.Rect.Y, (int)(2 * tic.Size), (int)chart.Rect.Height);
if ((this._ownerAxis as YAxis).Index != 0)
{//Draw the vertical line for yAxes that dont border the pChart area and so dont have one by default.
_ticsArray[k].X = 0;
_ticsArray[k + 1].X = 0;
_ticsArray[k].Y = -1;
_ticsArray[k + 1].Y = 1;
k += 2;
}
}
_linesShader.Use();//use Shader, bind VAO, bind VBO and give the tic values to the VBO
GL.BindVertexArray(_VAO);
GL.BindBuffer(BufferTarget.ArrayBuffer, _VBO);
GL.BufferData <Vector2>(BufferTarget.ArrayBuffer, (IntPtr)(Vector2.SizeInBytes * _ticsArray.Length), _ticsArray, BufferUsageHint.StaticDraw);
GL.VertexAttribPointer(_linesShader.VertexLocation, 2, VertexAttribPointerType.Float, false, Vector2.SizeInBytes, 0);
GL.Uniform4(_linesShader.ColorLocation, Color.Black);//set uniform variables Color and Transformationmatrix
GL.UniformMatrix4(_linesShader.MatrixLocation, false, ref _mat);
GL.DrawArrays(PrimitiveType.Lines, 0, k);//draw the lines
GL.BindVertexArray(0);
_linesShader.StopUse();
}
