nekohook/modules/source2013/sdk/materialsystem/stdshaders/common_lightmappedgeneric_fxc.h

//========= Copyright Valve Corporation, All rights reserved. ============//

#if defined(_X360)

void GetBaseTextureAndNormal(sampler base, sampler base2, sampler bump,
                             bool bBase2, bool bBump, float3 coords,
                             float3 vWeights, out float4 vResultBase,
                             out float4 vResultBase2, out float4 vResultBump) {
    vResultBase = 0;
    vResultBase2 = 0;
    vResultBump = 0;

    if (!bBump) {
        vResultBump = float4(0, 0, 1, 1);
    }

#if SEAMLESS

    vWeights = max(vWeights - 0.3, 0);

    vWeights *= 1.0f / dot(vWeights, float3(1, 1, 1));

    [branch] if (vWeights.x > 0) {
        vResultBase += vWeights.x * tex2D(base, coords.zy);

        if (bBase2) {
            vResultBase2 += vWeights.x * tex2D(base2, coords.zy);
        }

        if (bBump) {
            vResultBump += vWeights.x * tex2D(bump, coords.zy);
        }
    }

    [branch] if (vWeights.y > 0) {
        vResultBase += vWeights.y * tex2D(base, coords.xz);

        if (bBase2) {
            vResultBase2 += vWeights.y * tex2D(base2, coords.xz);
        }
        if (bBump) {
            vResultBump += vWeights.y * tex2D(bump, coords.xz);
        }
    }

    [branch] if (vWeights.z > 0) {
        vResultBase += vWeights.z * tex2D(base, coords.xy);
        if (bBase2) {
            vResultBase2 += vWeights.z * tex2D(base2, coords.xy);
        }

        if (bBump) {
            vResultBump += vWeights.z * tex2D(bump, coords.xy);
        }
    }

#else  // not seamless

    vResultBase = tex2D(base, coords.xy);

    if (bBase2) {
        vResultBase2 = tex2D(base2, coords.xy);
    }

    if (bBump) {
        vResultBump = tex2D(bump, coords.xy);
    }

#endif
}

#else  // PC

void GetBaseTextureAndNormal(sampler base, sampler base2, sampler bump,
                             bool bBase2, bool bBump, float3 coords,
                             float3 vWeights, out float4 vResultBase,
                             out float4 vResultBase2, out float4 vResultBump) {
    vResultBase = 0;
    vResultBase2 = 0;
    vResultBump = 0;

    if (!bBump) {
        vResultBump = float4(0, 0, 1, 1);
    }

#if SEAMLESS

    vResultBase += vWeights.x * tex2D(base, coords.zy);
    if (bBase2) {
        vResultBase2 += vWeights.x * tex2D(base2, coords.zy);
    }
    if (bBump) {
        vResultBump += vWeights.x * tex2D(bump, coords.zy);
    }

    vResultBase += vWeights.y * tex2D(base, coords.xz);
    if (bBase2) {
        vResultBase2 += vWeights.y * tex2D(base2, coords.xz);
    }
    if (bBump) {
        vResultBump += vWeights.y * tex2D(bump, coords.xz);
    }

    vResultBase += vWeights.z * tex2D(base, coords.xy);
    if (bBase2) {
        vResultBase2 += vWeights.z * tex2D(base2, coords.xy);
    }
    if (bBump) {
        vResultBump += vWeights.z * tex2D(bump, coords.xy);
    }

#else  // not seamless

    vResultBase = tex2D(base, coords.xy);
    if (bBase2) {
        vResultBase2 = tex2D(base2, coords.xy);
    }
    if (bBump) {
        vResultBump = tex2D(bump, coords.xy);
    }
#endif
}

#endif

float3 LightMapSample(sampler LightmapSampler, float2 vTexCoord) {
#if (!defined(_X360) || !defined(USE_32BIT_LIGHTMAPS_ON_360))
    {
        float3 sample = tex2D(LightmapSampler, vTexCoord);

        return sample;
    }
#else
    {
#if 0  // 1 for cheap sampling, 0 for accurate scaling from the individual
       // samples
		{
			float4 sample = tex2D( LightmapSampler, vTexCoord );

			return sample.rgb * sample.a;
		}
#else
        {
            float4 Weights;
            float4 samples_0;  // no arrays allowed in inline assembly
            float4 samples_1;
            float4 samples_2;
            float4 samples_3;

            asm {
				tfetch2D samples_0, vTexCoord.xy, LightmapSampler, OffsetX = -0.5, OffsetY = -0.5, MinFilter=point, MagFilter=point, MipFilter=keep, UseComputedLOD=false
				tfetch2D samples_1, vTexCoord.xy, LightmapSampler, OffsetX =  0.5, OffsetY = -0.5, MinFilter=point, MagFilter=point, MipFilter=keep, UseComputedLOD=false
				tfetch2D samples_2, vTexCoord.xy, LightmapSampler, OffsetX = -0.5, OffsetY =  0.5, MinFilter=point, MagFilter=point, MipFilter=keep, UseComputedLOD=false
				tfetch2D samples_3, vTexCoord.xy, LightmapSampler, OffsetX =  0.5, OffsetY =  0.5, MinFilter=point, MagFilter=point, MipFilter=keep, UseComputedLOD=false

				getWeights2D Weights, vTexCoord.xy, LightmapSampler
            }
            ;

            Weights = float4(
                (1 - Weights.x) * (1 - Weights.y), Weights.x * (1 - Weights.y),
                (1 - Weights.x) * Weights.y, Weights.x * Weights.y);

            float3 result;
            result.rgb = samples_0.rgb * (samples_0.a * Weights.x);
            result.rgb += samples_1.rgb * (samples_1.a * Weights.y);
            result.rgb += samples_2.rgb * (samples_2.a * Weights.z);
            result.rgb += samples_3.rgb * (samples_3.a * Weights.w);

            return result;
        }
#endif
    }
#endif
}