#region File Description
#endregion
namespace
Microsoft.Xna.Framework.Graphics
{
/// <summary>
/// Built-in effect that supports two-layer multitexturing.
/// </summary>
public
class
DualTextureEffect : Effect, IEffectMatrices, IEffectFog
{
#region Effect Parameters
EffectParameter textureParam;
EffectParameter texture2Param;
EffectParameter diffuseColorParam;
EffectParameter fogColorParam;
EffectParameter fogVectorParam;
EffectParameter worldViewProjParam;
EffectParameter shaderIndexParam;
#endregion
#region Fields
bool
fogEnabled;
bool
vertexColorEnabled;
Matrix world = Matrix.Identity;
Matrix view = Matrix.Identity;
Matrix projection = Matrix.Identity;
Matrix worldView;
Vector3 diffuseColor = Vector3.One;
float
alpha = 1;
float
fogStart = 0;
float
fogEnd = 1;
EffectDirtyFlags dirtyFlags = EffectDirtyFlags.All;
#endregion
#region Public Properties
/// <summary>
/// Gets or sets the world matrix.
/// </summary>
public
Matrix World
{
get
{
return
world; }
set
{
world = value;
dirtyFlags |= EffectDirtyFlags.WorldViewProj | EffectDirtyFlags.Fog;
}
}
/// <summary>
/// Gets or sets the view matrix.
/// </summary>
public
Matrix View
{
get
{
return
view; }
set
{
view = value;
dirtyFlags |= EffectDirtyFlags.WorldViewProj | EffectDirtyFlags.Fog;
}
}
/// <summary>
/// Gets or sets the projection matrix.
/// </summary>
public
Matrix Projection
{
get
{
return
projection; }
set
{
projection = value;
dirtyFlags |= EffectDirtyFlags.WorldViewProj;
}
}
/// <summary>
/// Gets or sets the material diffuse color (range 0 to 1).
/// </summary>
public
Vector3 DiffuseColor
{
get
{
return
diffuseColor; }
set
{
diffuseColor = value;
dirtyFlags |= EffectDirtyFlags.MaterialColor;
}
}
/// <summary>
/// Gets or sets the material alpha.
/// </summary>
public
float
Alpha
{
get
{
return
alpha; }
set
{
alpha = value;
dirtyFlags |= EffectDirtyFlags.MaterialColor;
}
}
/// <summary>
/// Gets or sets the fog enable flag.
/// </summary>
public
bool
FogEnabled
{
get
{
return
fogEnabled; }
set
{
if
(fogEnabled != value)
{
fogEnabled = value;
dirtyFlags |= EffectDirtyFlags.ShaderIndex | EffectDirtyFlags.FogEnable;
}
}
}
/// <summary>
/// Gets or sets the fog start distance.
/// </summary>
public
float
FogStart
{
get
{
return
fogStart; }
set
{
fogStart = value;
dirtyFlags |= EffectDirtyFlags.Fog;
}
}
/// <summary>
/// Gets or sets the fog end distance.
/// </summary>
public
float
FogEnd
{
get
{
return
fogEnd; }
set
{
fogEnd = value;
dirtyFlags |= EffectDirtyFlags.Fog;
}
}
/// <summary>
/// Gets or sets the fog color.
/// </summary>
public
Vector3 FogColor
{
get
{
return
fogColorParam.GetValueVector3(); }
set
{ fogColorParam.SetValue(value); }
}
/// <summary>
/// Gets or sets the current base texture.
/// </summary>
public
Texture2D Texture
{
get
{
return
textureParam.GetValueTexture2D(); }
set
{ textureParam.SetValue(value); }
}
/// <summary>
/// Gets or sets the current overlay texture.
/// </summary>
public
Texture2D Texture2
{
get
{
return
texture2Param.GetValueTexture2D(); }
set
{ texture2Param.SetValue(value); }
}
/// <summary>
/// Gets or sets whether vertex color is enabled.
/// </summary>
public
bool
VertexColorEnabled
{
get
{
return
vertexColorEnabled; }
set
{
if
(vertexColorEnabled != value)
{
vertexColorEnabled = value;
dirtyFlags |= EffectDirtyFlags.ShaderIndex;
}
}
}
#endregion
#region Methods
/// <summary>
/// Creates a new DualTextureEffect with default parameter settings.
/// </summary>
public
DualTextureEffect(GraphicsDevice device)
:
base
(device, Resources.DualTextureEffect)
{
CacheEffectParameters();
}
/// <summary>
/// Creates a new DualTextureEffect by cloning parameter settings from an existing instance.
/// </summary>
protected
DualTextureEffect(DualTextureEffect cloneSource)
:
base
(cloneSource)
{
CacheEffectParameters();
fogEnabled = cloneSource.fogEnabled;
vertexColorEnabled = cloneSource.vertexColorEnabled;
world = cloneSource.world;
view = cloneSource.view;
projection = cloneSource.projection;
diffuseColor = cloneSource.diffuseColor;
alpha = cloneSource.alpha;
fogStart = cloneSource.fogStart;
fogEnd = cloneSource.fogEnd;
}
/// <summary>
/// Creates a clone of the current DualTextureEffect instance.
/// </summary>
public
override
Effect Clone()
{
return
new
DualTextureEffect(
this
);
}
/// <summary>
/// Looks up shortcut references to our effect parameters.
/// </summary>
void
CacheEffectParameters()
{
textureParam = Parameters[
"Texture"
];
texture2Param = Parameters[
"Texture2"
];
diffuseColorParam = Parameters[
"DiffuseColor"
];
fogColorParam = Parameters[
"FogColor"
];
fogVectorParam = Parameters[
"FogVector"
];
worldViewProjParam = Parameters[
"WorldViewProj"
];
shaderIndexParam = Parameters[
"ShaderIndex"
];
}
/// <summary>
/// Lazily computes derived parameter values immediately before applying the effect.
/// </summary>
protected
internal
override
void
OnApply()
{
dirtyFlags = EffectHelpers.SetWorldViewProjAndFog(dirtyFlags,
ref
world,
ref
view,
ref
projection,
ref
worldView, fogEnabled, fogStart, fogEnd, worldViewProjParam, fogVectorParam);
if
((dirtyFlags & EffectDirtyFlags.MaterialColor) != 0)
{
diffuseColorParam.SetValue(
new
Vector4(diffuseColor * alpha, alpha));
dirtyFlags &= ~EffectDirtyFlags.MaterialColor;
}
if
((dirtyFlags & EffectDirtyFlags.ShaderIndex) != 0)
{
int
shaderIndex = 0;
if
(!fogEnabled)
shaderIndex += 1;
if
(vertexColorEnabled)
shaderIndex += 2;
shaderIndexParam.SetValue(shaderIndex);
dirtyFlags &= ~EffectDirtyFlags.ShaderIndex;
}
}
#endregion
}
}