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2026-11-07 13:30:45 +07:00

281 lines
8.1 KiB
HLSL

//-----------------------------------------------------------------------------
// File: ShadowMap.fx
//
// Desc: Effect file for high dynamic range cube mapping sample.
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//-----------------------------------------------------------------------------
#define SMAP_SIZE 512
#define SHADOW_EPSILON 0.00005f
float4x4 g_mWorldView;
float4x4 g_mProj;
float4x4 g_mViewToLightProj; // Transform from view space to light projection space
float4 g_vMaterial;
texture g_txScene;
texture g_txShadow;
float3 g_vLightPos; // Light position in view space
float3 g_vLightDir; // Light direction in view space
float4 g_vLightDiffuse = float4( 1.0f, 1.0f, 1.0f, 1.0f ); // Light diffuse color
float4 g_vLightAmbient = float4( 0.3f, 0.3f, 0.3f, 1.0f ); // Use an ambient light of 0.3
float g_fCosTheta; // Cosine of theta of the spot light
sampler2D g_samScene =
sampler_state
{
Texture = <g_txScene>;
MinFilter = Point;
MagFilter = Linear;
MipFilter = Linear;
};
sampler2D g_samShadow =
sampler_state
{
Texture = <g_txShadow>;
MinFilter = Point;
MagFilter = Point;
MipFilter = Point;
AddressU = Clamp;
AddressV = Clamp;
};
//-----------------------------------------------------------------------------
// Vertex Shader: VertScene
// Desc: Process vertex for scene
//-----------------------------------------------------------------------------
void VertScene( float4 iPos : POSITION,
float3 iNormal : NORMAL,
float2 iTex : TEXCOORD0,
out float4 oPos : POSITION,
out float2 Tex : TEXCOORD0,
out float4 vPos : TEXCOORD1,
out float3 vNormal : TEXCOORD2,
out float4 vPosLight : TEXCOORD3 )
{
//
// Transform position to view space
//
vPos = mul( iPos, g_mWorldView );
//
// Transform to screen coord
//
oPos = mul( vPos, g_mProj );
//
// Compute view space normal
//
vNormal = mul( iNormal, (float3x3)g_mWorldView );
//
// Propagate texture coord
//
Tex = iTex;
//
// Transform the position to light projection space, or the
// projection space as if the camera is looking out from
// the spotlight.
//
vPosLight = mul( vPos, g_mViewToLightProj );
}
//-----------------------------------------------------------------------------
// Pixel Shader: PixScene
// Desc: Process pixel (do per-pixel lighting) for enabled scene
//-----------------------------------------------------------------------------
float4 PixScene( float2 Tex : TEXCOORD0,
float4 vPos : TEXCOORD1,
float3 vNormal : TEXCOORD2,
float4 vPosLight : TEXCOORD3 ) : COLOR
{
float4 Diffuse;
// vLight is the unit vector from the light to this pixel
float3 vLight = normalize( float3( vPos - g_vLightPos ) );
// Compute diffuse from the light
if( dot( vLight, g_vLightDir ) > g_fCosTheta ) // Light must face the pixel (within Theta)
{
// Pixel is in lit area. Find out if it's
// in shadow using 2x2 percentage closest filtering
//transform from RT space to texture space.
float2 ShadowTexC = 0.5 * vPosLight.xy / vPosLight.w + float2( 0.5, 0.5 );
ShadowTexC.y = 1.0f - ShadowTexC.y;
// transform to texel space
float2 texelpos = SMAP_SIZE * ShadowTexC;
// Determine the lerp amounts
float2 lerps = frac( texelpos );
//read in bilerp stamp, doing the shadow checks
float sourcevals[4];
sourcevals[0] = (tex2D( g_samShadow, ShadowTexC ) + SHADOW_EPSILON < vPosLight.z / vPosLight.w)? 0.0f: 1.0f;
sourcevals[1] = (tex2D( g_samShadow, ShadowTexC + float2(1.0/SMAP_SIZE, 0) ) + SHADOW_EPSILON < vPosLight.z / vPosLight.w)? 0.0f: 1.0f;
sourcevals[2] = (tex2D( g_samShadow, ShadowTexC + float2(0, 1.0/SMAP_SIZE) ) + SHADOW_EPSILON < vPosLight.z / vPosLight.w)? 0.0f: 1.0f;
sourcevals[3] = (tex2D( g_samShadow, ShadowTexC + float2(1.0/SMAP_SIZE, 1.0/SMAP_SIZE) ) + SHADOW_EPSILON < vPosLight.z / vPosLight.w)? 0.0f: 1.0f;
// lerp between the shadow values to calculate our light amount
float LightAmount = lerp( lerp( sourcevals[0], sourcevals[1], lerps.x ),
lerp( sourcevals[2], sourcevals[3], lerps.x ),
lerps.y );
// Light it
Diffuse = ( saturate( dot( -vLight, normalize( vNormal ) ) ) * LightAmount * ( 1 - g_vLightAmbient ) + g_vLightAmbient )
* g_vMaterial;
} else
{
Diffuse = g_vLightAmbient * g_vMaterial;
}
return tex2D( g_samScene, Tex ) * Diffuse;
}
//-----------------------------------------------------------------------------
// Vertex Shader: VertLight
// Desc: Process vertex for the light object
//-----------------------------------------------------------------------------
void VertLight( float4 iPos : POSITION,
float3 iNormal : NORMAL,
float2 iTex : TEXCOORD0,
out float4 oPos : POSITION,
out float2 Tex : TEXCOORD0 )
{
//
// Transform position to view space
//
oPos = mul( iPos, g_mWorldView );
//
// Transform to screen coord
//
oPos = mul( oPos, g_mProj );
//
// Propagate texture coord
//
Tex = iTex;
}
//-----------------------------------------------------------------------------
// Pixel Shader: PixLight
// Desc: Process pixel for the light object
//-----------------------------------------------------------------------------
float4 PixLight( float2 Tex : TEXCOORD0,
float4 vPos : TEXCOORD1 ) : COLOR
{
return tex2D( g_samScene, Tex );
}
//-----------------------------------------------------------------------------
// Vertex Shader: VertShadow
// Desc: Process vertex for the shadow map
//-----------------------------------------------------------------------------
void VertShadow( float4 Pos : POSITION,
float3 Normal : NORMAL,
out float4 oPos : POSITION,
out float2 Depth : TEXCOORD0 )
{
//
// Compute the projected coordinates
//
oPos = mul( Pos, g_mWorldView );
oPos = mul( oPos, g_mProj );
//
// Store z and w in our spare texcoord
//
Depth.xy = oPos.zw;
}
//-----------------------------------------------------------------------------
// Pixel Shader: PixShadow
// Desc: Process pixel for the shadow map
//-----------------------------------------------------------------------------
void PixShadow( float2 Depth : TEXCOORD0,
out float4 Color : COLOR )
{
//
// Depth is z / w
//
Color = Depth.x / Depth.y;
}
//-----------------------------------------------------------------------------
// Technique: RenderScene
// Desc: Renders scene objects
//-----------------------------------------------------------------------------
technique RenderScene
{
pass p0
{
VertexShader = compile vs_2_0 VertScene();
PixelShader = compile ps_2_0 PixScene();
}
}
//-----------------------------------------------------------------------------
// Technique: RenderLight
// Desc: Renders the light object
//-----------------------------------------------------------------------------
technique RenderLight
{
pass p0
{
VertexShader = compile vs_2_0 VertLight();
PixelShader = compile ps_2_0 PixLight();
}
}
//-----------------------------------------------------------------------------
// Technique: RenderShadow
// Desc: Renders the shadow map
//-----------------------------------------------------------------------------
technique RenderShadow
{
pass p0
{
VertexShader = compile vs_2_0 VertShadow();
PixelShader = compile ps_2_0 PixShadow();
}
}