// --- render a single face ---
/// <summary>Renders a face of a face-vertex mesh.</summary>
/// <param name="mesh">The face-vertex mesh.</param>
/// <param name="faceIndex">The face of the mesh to render.</param>
/// <param name="position">The position of the face.</param>
/// <param name="orientation">The orientation of the face.</param>
/// <param name="state">The current OpenGL state.</param>
/// <remarks>This function may change the texture or emissive color in the current OpenGL state.</remarks>
private static void RenderFace(OpenBveApi.Geometry.FaceVertexMesh mesh, int faceIndex, OpenBveApi.Math.Vector3 position, OpenBveApi.Math.Orientation3 orientation, ref OpenGlState state)
{
int material = mesh.Faces[faceIndex].Material;
/*
* Set the texture.
* */
Textures.ApiHandle apiHandle = mesh.Materials[material].DaytimeTexture as Textures.ApiHandle;
int textureIndex = apiHandle != null ? apiHandle.TextureIndex : -1;
if (textureIndex >= 0 && Textures.RegisteredTextures[textureIndex].Status == Textures.TextureStatus.Loaded) {
int openGlTextureIndex = Textures.RegisteredTextures[textureIndex].OpenGlTextureIndex;
state.BindTexture(openGlTextureIndex);
} else {
state.UnbindTexture();
}
/*
* Begin rendering the face.
* */
switch (mesh.Faces[faceIndex].Type) {
case OpenBveApi.Geometry.FaceType.Triangles:
Gl.glBegin(Gl.GL_TRIANGLES);
break;
case OpenBveApi.Geometry.FaceType.TriangleStrip:
Gl.glBegin(Gl.GL_TRIANGLE_STRIP);
break;
case OpenBveApi.Geometry.FaceType.TriangleFan:
Gl.glBegin(Gl.GL_TRIANGLE_FAN);
break;
case OpenBveApi.Geometry.FaceType.Quads:
Gl.glBegin(Gl.GL_QUADS);
break;
case OpenBveApi.Geometry.FaceType.QuadStrip:
Gl.glBegin(Gl.GL_QUAD_STRIP);
break;
case OpenBveApi.Geometry.FaceType.Polygon:
Gl.glBegin(Gl.GL_POLYGON);
break;
default:
throw new InvalidOperationException();
}
/*
* Set the emissive color.
* */
OpenBveApi.Color.ColorRGB emissiveColor = mesh.Materials[material].EmissiveColor;
state.SetEmissiveColor(emissiveColor);
/*
* Render the vertices of the face.
* */
for (int j = 0; j < mesh.Faces[faceIndex].Vertices.Length; j++) {
int vertex = mesh.Faces[faceIndex].Vertices[j];
OpenBveApi.Math.Vector3 spatialCoordinates = mesh.Vertices[vertex].SpatialCoordinates;
spatialCoordinates.Rotate(orientation);
spatialCoordinates.Translate(position);
OpenBveApi.Math.Vector3 normal = mesh.Vertices[vertex].Normal;
normal.Rotate(orientation);
Gl.glColor4f(mesh.Vertices[vertex].ReflectiveColor.R, mesh.Vertices[vertex].ReflectiveColor.G, mesh.Vertices[vertex].ReflectiveColor.B, mesh.Vertices[vertex].ReflectiveColor.A);
Gl.glNormal3d(normal.X, normal.Y, normal.Z);
Gl.glTexCoord2d(mesh.Vertices[vertex].TextureCoordinates.X, mesh.Vertices[vertex].TextureCoordinates.Y);
Gl.glVertex3d(spatialCoordinates.X, spatialCoordinates.Y, spatialCoordinates.Z);
}
/*
* End rendering the face.
* */
Gl.glEnd();
}
