I'm a green horn with XNA and I've been trying to get past this issue for several days but every time I try to get it done I get an exception or the application just plain exits and it has been very irritating.
I want to be able to draw a 3D primitive without having to have a model premade for it. I had this code first:
VertexPositionColor[] primitiveList = { new VertexPositionColor(
new Vector3(1,1,0), Color.White), new VertexPositionColor(
new Vector3(0,1,-1), Color.White) };
short[] lineListIndices = { 0, 1 };
Controller.CurrentGame.GraphicsDevice.DrawUserIndexedPrimitives<VertexPositionColor>(
PrimitiveType.LineList,
primitiveList,
0, // vertex buffer offset to add to each element of the index buffer
2, // number of vertices in pointList
lineListIndices, // the index buffer
0, // first index element to read
1 // number of primitives to draw
);
And I get an InvalidOperationException with the following
Message "Both a vertex shader and pixel shader must be set on the device before any draw operations may be performed."
So then I try following the instructions on http://msdn.microsoft.com/en-us/library/bb203926.aspx and end up with the following code:
BasicEffect basicEffect = new BasicEffect(Controller.Graphics.GraphicsDevice);
basicEffect.World = Matrix.Identity;
basicEffect.View = Controller.Cam.view;
basicEffect.Projection = Controller.Cam.projection;
// primitive color
basicEffect.AmbientLightColor = new Vector3(0.1f, 0.1f, 0.1f);
basicEffect.DiffuseColor = new Vector3(1.0f, 1.0f, 1.0f);
basicEffect.SpecularColor = new Vector3(0.25f, 0.25f, 0.25f);
basicEffect.SpecularPower = 5.0f;
basicEffect.Alpha = 1.0f;
basicEffect.LightingEnabled = true;
if (basicEffect.LightingEnabled)
{
basicEffect.DirectionalLight0.Enabled = true; // enable each light individually
if (basicEffect.DirectionalLight0.Enabled)
{
// x direction
basicEffect.DirectionalLight0.DiffuseColor = new Vector3(1, 0, 0); // range is 0 to 1
basicEffect.DirectionalLight0.Direction = Vector3.Normalize(new Vector3(-1, 0, 0));
// points from the light to the origin of the scene
basicEffect.DirectionalLight0.SpecularColor = Vector3.One;
}
basicEffect.DirectionalLight1.Enabled = true;
if (basicEffect.DirectionalLight1.Enabled)
{
// y direction
basicEffect.DirectionalLight1.DiffuseColor = new Vector3(0, 0.75f, 0);
basicEffect.DirectionalLight1.Direction = Vector3.Normalize(new Vector3(0, -1, 0));
basicEffect.DirectionalLight1.SpecularColor = Vector3.One;
}
basicEffect.DirectionalLight2.Enabled = true;
if (basicEffect.DirectionalLight2.Enabled)
{
// z direction
basicEffect.DirectionalLight2.DiffuseColor = new Vector3(0, 0, 0.5f);
basicEffect.DirectionalLight2.Direction = Vector3.Normalize(new Vector3(0, 0, -1));
basicEffect.DirectionalLight2.SpecularColor = Vector3.One;
}
}
VertexDeclaration vertexDeclaration = new VertexDeclaration(new VertexElement[]
{
new VertexElement(0, VertexElementFormat.Vector3, VertexElementUsage.Position, 0),
new VertexElement(12, VertexElementFormat.Vector3, VertexElementUsage.Normal, 0),
new VertexElement(24, VertexElementFormat.Vector2, VertexElementUsage.TextureCoordinate, 0)
}
);
Vector3 topLeftFront = new Vector3(-1.0f, 1.0f, 1.0f);
Vector3 bottomLeftFront = new Vector3(-1.0f, -1.0f, 1.0f);
Vector3 topRightFront = new Vector3(1.0f, 1.0f, 1.0f);
Vector3 bottomRightFront = new Vector3(1.0f, -1.0f, 1.0f);
Vector3 topLeftBack = new Vector3(-1.0f, 1.0f, -1.0f);
Vector3 topRightBack = new Vector3(1.0f, 1.0f, -1.0f);
Vector3 bottomLeftBack = new Vector3(-1.0f, -1.0f, -1.0f);
Vector3 bottomRightBack = new Vector3(1.0f, -1.0f, -1.0f);
Vector2 textureTopLeft = new Vector2(0.0f, 0.0f);
Vector2 textureTopRight = new Vector2(1.0f, 0.0f);
Vector2 textureBottomLeft = new Vector2(0.0f, 1.0f);
Vector2 textureBottomRight = new Vector2(1.0f, 1.0f);
Vector3 frontNormal = new Vector3(0.0f, 0.0f, 1.0f);
Vector3 backNormal = new Vector3(0.0f, 0.0f, -1.0f);
Vector3 topNormal = new Vector3(0.0f, 1.0f, 0.0f);
Vector3 bottomNormal = new Vector3(0.0f, -1.0f, 0.0f);
Vector3 leftNormal = new Vector3(-1.0f, 0.0f, 0.0f);
Vector3 rightNormal = new Vector3(1.0f, 0.0f, 0.0f);
VertexPositionNormalTexture[] cubeVertices = new VertexPositionNormalTexture[6];
// Front face.
cubeVertices[0] =
new VertexPositionNormalTexture(
topLeftFront, frontNormal, textureTopLeft);
cubeVertices[1] =
new VertexPositionNormalTexture(
bottomLeftFront, frontNormal, textureBottomLeft);
cubeVertices[2] =
new VertexPositionNormalTexture(
topRightFront, frontNormal, textureTopRight);
cubeVertices[3] =
new VertexPositionNormalTexture(
bottomLeftFront, frontNormal, textureBottomLeft);
cubeVertices[4] =
new VertexPositionNormalTexture(
bottomRightFront, frontNormal, textureBottomRight);
cubeVertices[5] =
new VertexPositionNormalTexture(
topRightFront, frontNormal, textureTopRight);
RasterizerState rasterizerState1 = new RasterizerState();
rasterizerState1.CullMode = CullMode.None;
Controller.Graphics.GraphicsDevice.RasterizerState = rasterizerState1;
foreach (EffectPass pass in basicEffect.CurrentTechnique.Passes)
{
pass.Apply();
Controller.Graphics.GraphicsDevice.DrawPrimitives(
PrimitiveType.TriangleList,
0,
12
);
}
And I get the following Exception
Message "A valid vertex buffer (and a valid index buffer if you are using indexed primitives) must be set on the device before any draw operations may be performed."
I know I shouldn't have all of this code in the same place, but I just want to be able to get something to draw so I can see how it works but nothing works and I can't seem to load any examples into VS.
As I've said I'm rather new and beyond the question I would also greatly appreciate any kind of reading material that would point in the right direction for 3D XNA. Thank you for reading.