C++ DirectX 9 Radial ( Pie ) menu [closed] - c++

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What would be the easiest way to render a radial menu ( with dynamic number of items ) in DirectX 9?
void DrawMenu(int x, int y, int radius, int width, int segments, LPDIRECT3DDEVICE9 dev){
Draw2DCircle(x, y, radius, D3DCOLOR_RGBA(0, 255, 255, 255), dev);
Draw2DCircle(x, y, radius-width, D3DCOLOR_RGBA(0, 255, 255, 255), dev);
float innerX, innerY, outerX, outerY;
float Theta;
for (int i = 0; i < segments; i++){
Theta = i * (2*PI / segments);
innerX = (radius - width)*cos(Theta) + x;
innerY = (radius - width)*sin(Theta) + y;
outerX = (radius)*cos(Theta) + x;
outerY = (radius)*sin(Theta) + y;
DrawLine(innerX, innerY, outerX, outerY, D3DCOLOR_RGBA(0, 255, 255, 255), dev);
}
}
I did as Mario said and it works like a charm, but... What would I need to do that menu would be colored?
Draving functions:
void DrawLine(int x1, int y1, int x2, int y2, D3DCOLOR color, LPDIRECT3DDEVICE9 dev){
D3DTLVERTEX Line[2];
Line[0] = CreateD3DTLVERTEX(x1, y1, 0.0f, 1.0f, color, 0.0f, 0.0f);
Line[1] = CreateD3DTLVERTEX(x2, y2, 0.0f, 1.0f, color, 0.0f, 0.0f);
dev->SetFVF(D3DFVF_TL);
dev->SetTexture(0, NULL);
dev->DrawPrimitiveUP(D3DPT_LINESTRIP, 2, &Line[0], sizeof(Line[0]));}
void Draw2DCircle(int x, int y, float radius, D3DCOLOR color, LPDIRECT3DDEVICE9 dev){
const int NUMPOINTS = 40;
D3DTLVERTEX Circle[NUMPOINTS + 1];
int i;
float X;
float Y;
float Theta;
float AngleBetweenPoints;
AngleBetweenPoints = (float)((2 * PI) / NUMPOINTS);
for (i = 0; i <= NUMPOINTS; i++)
{
Theta = i * AngleBetweenPoints;
X = (float)(x + radius * cos(Theta));
Y = (float)(y - radius * sin(Theta));
Circle[i] = CreateD3DTLVERTEX(X, Y, 0.0f, 1.0f, color, 0.0f, 0.0f);
}
dev->SetFVF(D3DFVF_TL);
dev->SetTexture(0, NULL);
dev->DrawPrimitiveUP(D3DPT_LINESTRIP, NUMPOINTS, &Circle[0], sizeof(Circle[0]));}
Custom vertex structure
struct D3DTLVERTEX{
float fX;
float fY;
float fZ;
float fRHW;
D3DCOLOR Color;
float fU;
float fV;};

Answer 1

For future questions, you should include some code, so people are able to help you pinpoint where you've made a mistake rather than (re-)writing everything from scratch.
Consider the following code untested pseudo code. You might need some more adjustments and/or fix a few bugs (writing this from memory; not with some dev environment running).
I'm going to draw an empty circle only. It should be trivial to extend this to draw a ring, which essentially just means adding a second, smaller circle.
To draw a circle, you'd typically use a fixed number of points. Let's assume we'd like to use at least 30.
With an equal distribution, this means we'll get 30 / number_of_segments points per segment. There's a problem however: There might be cases where the ending of a segment should be between two points, so it's better to use 30 / number_of_segments + 1 points for each segment.
Once this is established, it's rather easy to define all points using polar coordinates:
The first point has an angle of start = segment_number * (360 / number_of_segments).
The last point has an angle of end = (segment_number + 1) * (360 / number_of_segments).
The remaining points are equally distributed between start and end.
To get cartesian coordinates you'd just use trigonometry (r is the radius, a the angle):
x = r * cos(a);
y = r * sin(a);
With all your points known, it should be easy to create some visible geometry with that. Keep in mind that you might have to add some offset to move the circle/ring as well.