/// <summary>
/// Draw all elements.
/// </summary>
/// <param name="ctx">
/// The <see cref="GraphicsContext"/> used for rendering.
/// </param>
/// <param name="shader">
/// The <see cref="ShaderProgram"/> used for drawing the vertex arrays.
/// </param>
public void Draw(GraphicsContext ctx, ShaderProgram shader)
{
Draw(ctx, shader, null);
}
/// <summary>
/// Draw a specific element set.
/// </summary>
/// <param name="ctx">
/// The <see cref="GraphicsContext"/> used for rendering.
/// </param>
/// <param name="shader">
/// The <see cref="ShaderProgram"/> used for drawing the vertex arrays.
/// </param>
/// <param name="elementIndex">
/// A <see cref="Int32"/> that specifies the index of the element to draw. If it is less than 0, it draws
/// all elements set. The index can be obtained by the value returned by <see cref="SetElementArray"/>.
/// </param>
public void Draw(GraphicsContext ctx, ShaderProgram shader, int elementIndex)
{
Draw(ctx, shader, GetElementArray(elementIndex));
}
/// <summary>
/// Set the vertex arrays state for the shader program.
/// </summary>
/// <param name="ctx">
/// A <see cref="GraphicsContext"/> on which the shader program is bound.
/// </param>
/// <param name="shaderProgram">
/// A <see cref="ShaderProgram"/> on which the vertex arrays shall be bound.
/// </param>
private void SetVertexArrayState(GraphicsContext ctx, ShaderProgram shaderProgram)
{
CheckThisExistence(ctx);
// Set vertex array state all at once...
ctx.Bind(this, true);
if (shaderProgram != null)
{
ICollection <string> activeAttributes = shaderProgram.ActiveAttributes;
uint attributesSet = 0;
// Set vertex array state
foreach (string attributeName in activeAttributes)
{
IVertexArray shaderVertexArray = GetVertexArray(attributeName, shaderProgram);
if (shaderVertexArray == null)
{
continue;
}
ShaderProgram.AttributeBinding attributeBinding = shaderProgram.GetActiveAttribute(attributeName);
IVertexArray currentVertexArray = _VertexArrayState[attributeBinding.Location];
//if (ReferenceEquals(shaderVertexArray, currentVertexArray) == false) {
shaderVertexArray.SetVertexAttribute(ctx, attributeBinding, attributeName);
_VertexArrayState[attributeBinding.Location] = shaderVertexArray;
//}
attributesSet++;
}
if (attributesSet == 0)
{
throw new InvalidOperationException("no attribute is set");
}
}
else
{
IVertexArray attributeArray;
// No shader program: using fixed pipeline program. ATM enable all attributes having a semantic
if ((attributeArray = GetVertexArray(VertexArraySemantic.Position)) == null)
{
throw new InvalidOperationException("no position semantic array defined");
}
attributeArray.SetVertexAttribute(ctx, null, VertexArraySemantic.Position);
// Optional attributes
if ((attributeArray = GetVertexArray(VertexArraySemantic.Color)) != null)
{
attributeArray.SetVertexAttribute(ctx, null, VertexArraySemantic.Color);
}
if ((attributeArray = GetVertexArray(VertexArraySemantic.Normal)) != null)
{
attributeArray.SetVertexAttribute(ctx, null, VertexArraySemantic.Normal);
}
if ((attributeArray = GetVertexArray(VertexArraySemantic.TexCoord)) != null)
{
attributeArray.SetVertexAttribute(ctx, null, VertexArraySemantic.TexCoord);
}
}
}
