private void SetState(State state, int requiredVertices, CanvasBrush brush)
{
if (brush == null)
throw new ArgumentNullException("brush");
this.EnsureDrawInProgress();
this.state = state;
this.brush = brush;
}
public void DrawCircle(Vector2 center, float radius, CanvasBrush brush)
{
this.SetState(State.Circle, 362, brush);
Vector2 modelPositionCenter = new Vector2(radius, radius);
Vector2 texCoordCenter = new Vector2(0.5f, 0.5f);
this.AddVertex(ref modelPositionCenter, ref center, ref texCoordCenter);
Vector2 topLeft = new Vector2(center.X - radius, center.Y - radius);
for (int i = 0; i <= 360; i++)
{
Vector2 screenPositionTemp = new Vector2(center.X, center.Y - radius);
Vector2 screenPosition;
RotateAboutOrigin(ref screenPositionTemp, ref center, MathHelper.ToRadians(i), out screenPosition);
Vector2 modelPosition = new Vector2(screenPosition.X - topLeft.X, screenPosition.Y - topLeft.Y);
Vector2 texCoordTemp = new Vector2(0.5f, 0.0f);
Vector2 texCoord;
RotateAboutOrigin(ref screenPositionTemp, ref texCoordCenter, MathHelper.ToRadians(i), out texCoord);
this.AddVertex(ref modelPosition, ref screenPosition, ref texCoord);
}
this.Flush();
}
public void End()
{
this.EnsureDrawInProgress();
this.brush = null;
this.drawInProgress = false;
}
private void DrawTriangleSet(State state, IList<Vector2> positions, CanvasBrush brush)
{
if (positions == null)
throw new ArgumentNullException("positions");
if (positions.Count < 3)
return;
this.SetState(state, positions.Count, brush);
Vector2 min = positions[0];
Vector2 max = positions[0];
for (int i = 1; i < positions.Count; i++)
{
if (positions[i].X < min.X)
min.X = positions[i].X;
if (positions[i].Y < min.Y)
min.Y = positions[i].Y;
if (positions[i].X > max.X)
max.X = positions[i].X;
if (positions[i].Y > max.Y)
max.Y = positions[i].Y;
}
float width = max.X - min.X;
float height = max.Y - min.Y;
for (int i = 0; i < positions.Count; i++)
{
Vector2 modelPosition = new Vector2(positions[i].X - min.X, positions[i].Y - min.Y);
Vector2 screenPosition = positions[i];
Vector2 texCoord = new Vector2(modelPosition.X / width, modelPosition.Y / height);
this.AddVertex(ref modelPosition, ref screenPosition, ref texCoord);
}
this.Flush();
}
public void DrawTriangleStrip(IList<Vector2> positions, CanvasBrush brush)
{
this.DrawTriangleSet(State.TriangleStrip, positions, brush);
}
public void DrawTriangle(Vector2 v1, Vector2 v2, Vector2 v3, CanvasBrush brush)
{
this.SetState(State.Triangle, 3, brush);
Vector2 min = v1;
Vector2 max = v1;
if (v2.X < min.X)
min.X = v2.X;
if (v2.X > max.X)
max.X = v2.X;
if (v3.X < min.X)
min.X = v3.X;
if (v3.X > max.X)
max.X = v3.X;
if (v2.Y < min.Y)
min.Y = v2.Y;
if (v2.Y > max.Y)
max.Y = v2.Y;
if (v3.Y < min.Y)
min.Y = v3.Y;
if (v3.Y > max.Y)
max.Y = v3.Y;
Vector2 modelPosition1 = new Vector2(v1.X - min.X, v1.Y - min.Y);
Vector2 modelPosition2 = new Vector2(v2.X - min.X, v2.Y - min.Y);
Vector2 modelPosition3 = new Vector2(v3.X - min.X, v3.Y - min.Y);
float width = max.X - min.X;
float height = max.Y - min.Y;
Vector2 texCoord1 = new Vector2(v1.X / width, v1.Y / height);
Vector2 texCoord2 = new Vector2(v2.X / width, v2.Y / height);
Vector2 texCoord3 = new Vector2(v3.X / width, v3.Y / height);
this.AddVertex(ref modelPosition1, ref v1, ref texCoord1);
this.AddVertex(ref modelPosition2, ref v2, ref texCoord2);
this.AddVertex(ref modelPosition3, ref v3, ref texCoord3);
this.Flush();
}
public void DrawRectangle(Rectangle rectangle, CanvasBrush brush)
{
this.DrawRectangle(new Vector2(rectangle.Left, rectangle.Top), new Vector2(rectangle.Right, rectangle.Bottom), brush);
}
public void DrawRectangle(Vector2 topLeft, Vector2 bottomRight, CanvasBrush brush)
{
this.SetState(State.Rectangle, 4, brush);
Vector2 topLeftModelPosition = Vector2.Zero;
Vector2 topLeftScreenPosition = topLeft;
Vector2 topLeftTexCoords = Vector2.Zero;
Vector2 topRightModelPosition = new Vector2(bottomRight.X - topLeft.X, 0);
Vector2 topRightScreenPosition = new Vector2(bottomRight.X, topLeft.Y);
Vector2 topRightTexCoords = Vector2.UnitX;
Vector2 bottomRightModelPosition = new Vector2(bottomRight.X - topLeft.X, bottomRight.Y - topLeft.Y);
Vector2 bottomRightScreenPosition = bottomRight;
Vector2 bottomRightTexCoords = Vector2.One;
Vector2 bottomLeftModelPosition = new Vector2(0, bottomRight.Y - topLeft.Y);
Vector2 bottomLeftScreenPosition = new Vector2(topLeft.X, bottomRight.Y);
Vector2 bottomLeftTexCoords = Vector2.UnitY;
this.AddVertex(ref topLeftModelPosition, ref topLeftScreenPosition, ref topLeftTexCoords);
this.AddVertex(ref topRightModelPosition, ref topRightScreenPosition, ref topRightTexCoords);
this.AddVertex(ref bottomLeftModelPosition, ref bottomLeftScreenPosition, ref bottomLeftTexCoords);
this.AddVertex(ref bottomRightModelPosition, ref bottomRightScreenPosition, ref bottomRightTexCoords);
this.Flush();
}
public void DrawLine(Vector2 start, Vector2 end, float width, CanvasBrush brush)
{
this.SetState(State.Line, 6, brush);
float distance;
Vector2.Distance(ref start, ref end, out distance);
float angle = (float)Math.Atan2(end.Y - start.Y, end.X - start.X);
float halfWidth = width / 2.0f;
Vector2 modelTopLeft = Vector2.Zero;
Vector2 modelTopRight = new Vector2(distance, 0);
Vector2 modelBottomRight = new Vector2(distance, width);
Vector2 modelBottomLeft = new Vector2(0, width);
Vector2 screenTopLeftTemp = new Vector2(start.X, start.Y - halfWidth);
Vector2 screenTopLeft;
RotateAboutOrigin(ref screenTopLeftTemp, ref start, angle, out screenTopLeft);
Vector2 screenTopRightTemp = new Vector2(start.X + distance, start.Y - halfWidth);
Vector2 screenTopRight;
RotateAboutOrigin(ref screenTopRightTemp, ref start, angle, out screenTopRight);
Vector2 screenBottomRightTemp = new Vector2(start.X + distance, start.Y + halfWidth);
Vector2 screenBottomRight;
RotateAboutOrigin(ref screenBottomRightTemp, ref start, angle, out screenBottomRight);
Vector2 screenBottomLeftTemp = new Vector2(start.X, start.Y + halfWidth);
Vector2 screenBottomLeft;
RotateAboutOrigin(ref screenBottomLeftTemp, ref start, angle, out screenBottomLeft);
Vector2 topLeftTexCoord = Vector2.Zero;
Vector2 topRightUV = Vector2.UnitX;
Vector2 bottomRightUV = Vector2.One;
Vector2 bottomLeftUV = Vector2.UnitY;
this.AddVertex(ref modelTopLeft, ref screenTopLeft, ref topLeftTexCoord);
this.AddVertex(ref modelTopRight, ref screenTopRight, ref topRightUV);
this.AddVertex(ref modelBottomLeft, ref screenBottomLeft, ref bottomLeftUV);
this.AddVertex(ref modelTopRight, ref screenTopRight, ref topRightUV);
this.AddVertex(ref modelBottomRight, ref screenBottomRight, ref bottomRightUV);
this.AddVertex(ref modelBottomLeft, ref screenBottomLeft, ref bottomLeftUV);
this.Flush();
}
