Merge pull request #2727 from wwylele/spot-light

Fragment lighting: implement spot light 

5 files changed, 128 insertions, 28 deletions

diff --git a/src/video_core/regs_lighting.h b/src/video_core/regs_lighting.h
index 6793405d9..fbfebc0a7 100644
--- a/src/video_core/regs_lighting.h
+++ b/src/video_core/regs_lighting.h
@@ -26,6 +26,16 @@ struct LightingRegs {
         DistanceAttenuation = 16,
     };
 
+    static LightingSampler SpotlightAttenuationSampler(unsigned index) {
+        return static_cast<LightingSampler>(
+            static_cast<unsigned>(LightingSampler::SpotlightAttenuation) + index);
+    }
+
+    static LightingSampler DistanceAttenuationSampler(unsigned index) {
+        return static_cast<LightingSampler>(
+            static_cast<unsigned>(LightingSampler::DistanceAttenuation) + index);
+    }
+
     /**
     * Pica fragment lighting supports using different LUTs for each lighting component:  Reflectance
     * R, G, and B channels, distribution function for specular components 0 and 1, fresnel factor,
@@ -73,6 +83,8 @@ struct LightingRegs {
         VH = 1, // Cosine of the angle between the view and half-angle vectors
         NV = 2, // Cosine of the angle between the normal and the view vector
         LN = 3, // Cosine of the angle between the light and the normal vectors
+        SP = 4, // Cosine of the angle between the light and the inverse spotlight vectors
+        CP = 5, // TODO: document and implement
     };
 
     enum class LightingBumpMode : u32 {
@@ -104,6 +116,9 @@ struct LightingRegs {
             return (config != LightingConfig::Config0) && (config != LightingConfig::Config1) &&
                    (config != LightingConfig::Config5);
 
+        case LightingSampler::SpotlightAttenuation:
+            return (config != LightingConfig::Config2) && (config != LightingConfig::Config3);
+
         case LightingSampler::Fresnel:
             return (config != LightingConfig::Config0) && (config != LightingConfig::Config2) &&
                    (config != LightingConfig::Config4);
@@ -116,11 +131,10 @@ struct LightingRegs {
             return (config == LightingConfig::Config4) || (config == LightingConfig::Config5) ||
                    (config == LightingConfig::Config7);
         default:
-            UNREACHABLE_MSG("Regs::IsLightingSamplerSupported: Reached "
-                            "unreachable section, sampler should be one "
-                            "of Distribution0, Distribution1, Fresnel, "
-                            "ReflectRed, ReflectGreen or ReflectBlue, instead "
-                            "got %i",
+            UNREACHABLE_MSG("Regs::IsLightingSamplerSupported: Reached unreachable section, "
+                            "sampler should be one of Distribution0, Distribution1, "
+                            "SpotlightAttenuation, Fresnel, ReflectRed, ReflectGreen or "
+                            "ReflectBlue, instead got %i",
                             static_cast<int>(config));
         }
     }
@@ -140,7 +154,16 @@ struct LightingRegs {
             BitField<0, 16, u32> z;
         };
 
-        INSERT_PADDING_WORDS(0x3);
+        // inverse spotlight direction vector, encoded as fixed1.1.11
+        union {
+            BitField<0, 13, s32> spot_x;
+            BitField<16, 13, s32> spot_y;
+        };
+        union {
+            BitField<0, 13, s32> spot_z;
+        };
+
+        INSERT_PADDING_WORDS(0x1);
 
         union {
             BitField<0, 1, u32> directional;
@@ -169,8 +192,16 @@ struct LightingRegs {
     } config0;
 
     union {
+        u32 raw;
+
+        // Each bit specifies whether spot light attenuation should be applied for the corresponding
+        // light.
+        BitField<8, 8, u32> disable_spot_atten;
+
         BitField<16, 1, u32> disable_lut_d0;
         BitField<17, 1, u32> disable_lut_d1;
+        // Note: by intuition, BitField<18, 1, u32> should be disable_lut_sp, but it is actually a
+        // dummy bit which is always set as 1.
         BitField<19, 1, u32> disable_lut_fr;
         BitField<20, 1, u32> disable_lut_rr;
         BitField<21, 1, u32> disable_lut_rg;
@@ -178,23 +209,15 @@ struct LightingRegs {
 
         // Each bit specifies whether distance attenuation should be applied for the corresponding
         // light.
-        BitField<24, 1, u32> disable_dist_atten_light_0;
-        BitField<25, 1, u32> disable_dist_atten_light_1;
-        BitField<26, 1, u32> disable_dist_atten_light_2;
-        BitField<27, 1, u32> disable_dist_atten_light_3;
-        BitField<28, 1, u32> disable_dist_atten_light_4;
-        BitField<29, 1, u32> disable_dist_atten_light_5;
-        BitField<30, 1, u32> disable_dist_atten_light_6;
-        BitField<31, 1, u32> disable_dist_atten_light_7;
+        BitField<24, 8, u32> disable_dist_atten;
     } config1;
 
     bool IsDistAttenDisabled(unsigned index) const {
-        const unsigned disable[] = {
-            config1.disable_dist_atten_light_0, config1.disable_dist_atten_light_1,
-            config1.disable_dist_atten_light_2, config1.disable_dist_atten_light_3,
-            config1.disable_dist_atten_light_4, config1.disable_dist_atten_light_5,
-            config1.disable_dist_atten_light_6, config1.disable_dist_atten_light_7};
-        return disable[index] != 0;
+        return (config1.disable_dist_atten & (1 << index)) != 0;
+    }
+
+    bool IsSpotAttenDisabled(unsigned index) const {
+        return (config1.disable_spot_atten & (1 << index)) != 0;
     }
 
     union {
diff --git a/src/video_core/renderer_opengl/gl_rasterizer.cpp b/src/video_core/renderer_opengl/gl_rasterizer.cpp
index aa9b831dd..57d5e8253 100644
--- a/src/video_core/renderer_opengl/gl_rasterizer.cpp
+++ b/src/video_core/renderer_opengl/gl_rasterizer.cpp
@@ -735,6 +735,40 @@ void RasterizerOpenGL::NotifyPicaRegisterChanged(u32 id) {
         SyncLightPosition(7);
         break;
 
+    // Fragment spot lighting direction
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[0].spot_x, 0x146 + 0 * 0x10):
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[0].spot_z, 0x147 + 0 * 0x10):
+        SyncLightSpotDirection(0);
+        break;
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[1].spot_x, 0x146 + 1 * 0x10):
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[1].spot_z, 0x147 + 1 * 0x10):
+        SyncLightSpotDirection(1);
+        break;
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[2].spot_x, 0x146 + 2 * 0x10):
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[2].spot_z, 0x147 + 2 * 0x10):
+        SyncLightSpotDirection(2);
+        break;
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[3].spot_x, 0x146 + 3 * 0x10):
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[3].spot_z, 0x147 + 3 * 0x10):
+        SyncLightSpotDirection(3);
+        break;
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[4].spot_x, 0x146 + 4 * 0x10):
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[4].spot_z, 0x147 + 4 * 0x10):
+        SyncLightSpotDirection(4);
+        break;
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[5].spot_x, 0x146 + 5 * 0x10):
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[5].spot_z, 0x147 + 5 * 0x10):
+        SyncLightSpotDirection(5);
+        break;
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[6].spot_x, 0x146 + 6 * 0x10):
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[6].spot_z, 0x147 + 6 * 0x10):
+        SyncLightSpotDirection(6);
+        break;
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[7].spot_x, 0x146 + 7 * 0x10):
+    case PICA_REG_INDEX_WORKAROUND(lighting.light[7].spot_z, 0x147 + 7 * 0x10):
+        SyncLightSpotDirection(7);
+        break;
+
     // Fragment lighting light source config
     case PICA_REG_INDEX_WORKAROUND(lighting.light[0].config, 0x149 + 0 * 0x10):
     case PICA_REG_INDEX_WORKAROUND(lighting.light[1].config, 0x149 + 1 * 0x10):
@@ -1595,6 +1629,17 @@ void RasterizerOpenGL::SyncLightPosition(int light_index) {
     }
 }
 
+void RasterizerOpenGL::SyncLightSpotDirection(int light_index) {
+    const auto& light = Pica::g_state.regs.lighting.light[light_index];
+    GLvec3 spot_direction = {light.spot_x / 2047.0f, light.spot_y / 2047.0f,
+                             light.spot_z / 2047.0f};
+
+    if (spot_direction != uniform_block_data.data.light_src[light_index].spot_direction) {
+        uniform_block_data.data.light_src[light_index].spot_direction = spot_direction;
+        uniform_block_data.dirty = true;
+    }
+}
+
 void RasterizerOpenGL::SyncLightDistanceAttenuationBias(int light_index) {
     GLfloat dist_atten_bias =
         Pica::float20::FromRaw(Pica::g_state.regs.lighting.light[light_index].dist_atten_bias)
diff --git a/src/video_core/renderer_opengl/gl_rasterizer.h b/src/video_core/renderer_opengl/gl_rasterizer.h
index a9ad7d660..d9a3e9d1c 100644
--- a/src/video_core/renderer_opengl/gl_rasterizer.h
+++ b/src/video_core/renderer_opengl/gl_rasterizer.h
@@ -125,6 +125,7 @@ private:
         alignas(16) GLvec3 diffuse;
         alignas(16) GLvec3 ambient;
         alignas(16) GLvec3 position;
+        alignas(16) GLvec3 spot_direction; // negated
         GLfloat dist_atten_bias;
         GLfloat dist_atten_scale;
     };
@@ -153,7 +154,7 @@ private:
     };
 
     static_assert(
-        sizeof(UniformData) == 0x3E0,
+        sizeof(UniformData) == 0x460,
         "The size of the UniformData structure has changed, update the structure in the shader");
     static_assert(sizeof(UniformData) < 16384,
                   "UniformData structure must be less than 16kb as per the OpenGL spec");
@@ -241,6 +242,9 @@ private:
     /// Syncs the specified light's position to match the PICA register
     void SyncLightPosition(int light_index);
 
+    /// Syncs the specified spot light direcition to match the PICA register
+    void SyncLightSpotDirection(int light_index);
+
     /// Syncs the specified light's distance attenuation bias to match the PICA register
     void SyncLightDistanceAttenuationBias(int light_index);
 
diff --git a/src/video_core/renderer_opengl/gl_shader_gen.cpp b/src/video_core/renderer_opengl/gl_shader_gen.cpp
index ffe419863..db53710aa 100644
--- a/src/video_core/renderer_opengl/gl_shader_gen.cpp
+++ b/src/video_core/renderer_opengl/gl_shader_gen.cpp
@@ -75,6 +75,8 @@ PicaShaderConfig PicaShaderConfig::BuildFromRegs(const Pica::Regs& regs) {
         state.lighting.light[light_index].two_sided_diffuse = light.config.two_sided_diffuse != 0;
         state.lighting.light[light_index].dist_atten_enable =
             !regs.lighting.IsDistAttenDisabled(num);
+        state.lighting.light[light_index].spot_atten_enable =
+            !regs.lighting.IsSpotAttenDisabled(num);
     }
 
     state.lighting.lut_d0.enable = regs.lighting.config1.disable_lut_d0 == 0;
@@ -87,6 +89,12 @@ PicaShaderConfig PicaShaderConfig::BuildFromRegs(const Pica::Regs& regs) {
     state.lighting.lut_d1.type = regs.lighting.lut_input.d1.Value();
     state.lighting.lut_d1.scale = regs.lighting.lut_scale.GetScale(regs.lighting.lut_scale.d1);
 
+    // this is a dummy field due to lack of the corresponding register
+    state.lighting.lut_sp.enable = true;
+    state.lighting.lut_sp.abs_input = regs.lighting.abs_lut_input.disable_sp == 0;
+    state.lighting.lut_sp.type = regs.lighting.lut_input.sp.Value();
+    state.lighting.lut_sp.scale = regs.lighting.lut_scale.GetScale(regs.lighting.lut_scale.sp);
+
     state.lighting.lut_fr.enable = regs.lighting.config1.disable_lut_fr == 0;
     state.lighting.lut_fr.abs_input = regs.lighting.abs_lut_input.disable_fr == 0;
     state.lighting.lut_fr.type = regs.lighting.lut_input.fr.Value();
@@ -509,7 +517,8 @@ static void WriteLighting(std::string& out, const PicaShaderConfig& config) {
     out += "vec4 diffuse_sum = vec4(0.0, 0.0, 0.0, 1.0);\n"
            "vec4 specular_sum = vec4(0.0, 0.0, 0.0, 1.0);\n"
            "vec3 light_vector = vec3(0.0);\n"
-           "vec3 refl_value = vec3(0.0);\n";
+           "vec3 refl_value = vec3(0.0);\n"
+           "vec3 spot_dir = vec3(0.0);\n;";
 
     // Compute fragment normals
     if (lighting.bump_mode == LightingRegs::LightingBumpMode::NormalMap) {
@@ -560,6 +569,10 @@ static void WriteLighting(std::string& out, const PicaShaderConfig& config) {
             index = std::string("dot(light_vector, normal)");
             break;
 
+        case LightingRegs::LightingLutInput::SP:
+            index = std::string("dot(light_vector, spot_dir)");
+            break;
+
         default:
             LOG_CRITICAL(HW_GPU, "Unknown lighting LUT input %d\n", (int)input);
             UNIMPLEMENTED();
@@ -596,21 +609,34 @@ static void WriteLighting(std::string& out, const PicaShaderConfig& config) {
         else
             out += "light_vector = normalize(" + light_src + ".position + view);\n";
 
+        out += "spot_dir = " + light_src + ".spot_direction;\n";
+
         // Compute dot product of light_vector and normal, adjust if lighting is one-sided or
         // two-sided
         std::string dot_product = light_config.two_sided_diffuse
                                       ? "abs(dot(light_vector, normal))"
                                       : "max(dot(light_vector, normal), 0.0)";
 
+        // If enabled, compute spot light attenuation value
+        std::string spot_atten = "1.0";
+        if (light_config.spot_atten_enable &&
+            LightingRegs::IsLightingSamplerSupported(
+                lighting.config, LightingRegs::LightingSampler::SpotlightAttenuation)) {
+            std::string index =
+                GetLutIndex(light_config.num, lighting.lut_sp.type, lighting.lut_sp.abs_input);
+            auto sampler = LightingRegs::SpotlightAttenuationSampler(light_config.num);
+            spot_atten = "(" + std::to_string(lighting.lut_sp.scale) + " * " +
+                         GetLutValue(sampler, index) + ")";
+        }
+
         // If enabled, compute distance attenuation value
         std::string dist_atten = "1.0";
         if (light_config.dist_atten_enable) {
             std::string index = "(" + light_src + ".dist_atten_scale * length(-view - " +
                                 light_src + ".position) + " + light_src + ".dist_atten_bias)";
             index = "(OFFSET_256 + SCALE_256 * clamp(" + index + ", 0.0, 1.0))";
-            const unsigned lut_num =
-                ((unsigned)LightingRegs::LightingSampler::DistanceAttenuation + light_config.num);
-            dist_atten = GetLutValue((LightingRegs::LightingSampler)lut_num, index);
+            auto sampler = LightingRegs::DistanceAttenuationSampler(light_config.num);
+            dist_atten = GetLutValue(sampler, index);
         }
 
         // If enabled, clamp specular component if lighting result is negative
@@ -711,11 +737,11 @@ static void WriteLighting(std::string& out, const PicaShaderConfig& config) {
 
         // Compute primary fragment color (diffuse lighting) function
         out += "diffuse_sum.rgb += ((" + light_src + ".diffuse * " + dot_product + ") + " +
-               light_src + ".ambient) * " + dist_atten + ";\n";
+               light_src + ".ambient) * " + dist_atten + " * " + spot_atten + ";\n";
 
         // Compute secondary fragment color (specular lighting) function
         out += "specular_sum.rgb += (" + specular_0 + " + " + specular_1 + ") * " +
-               clamp_highlights + " * " + dist_atten + ";\n";
+               clamp_highlights + " * " + dist_atten + " * " + spot_atten + ";\n";
     }
 
     // Sum final lighting result
@@ -967,6 +993,7 @@ struct LightSrc {
     vec3 diffuse;
     vec3 ambient;
     vec3 position;
+    vec3 spot_direction;
     float dist_atten_bias;
     float dist_atten_scale;
 };
diff --git a/src/video_core/renderer_opengl/gl_shader_gen.h b/src/video_core/renderer_opengl/gl_shader_gen.h
index ea6d216d1..9c90eadf9 100644
--- a/src/video_core/renderer_opengl/gl_shader_gen.h
+++ b/src/video_core/renderer_opengl/gl_shader_gen.h
@@ -93,6 +93,7 @@ union PicaShaderConfig {
                 bool directional;
                 bool two_sided_diffuse;
                 bool dist_atten_enable;
+                bool spot_atten_enable;
             } light[8];
 
             bool enable;
@@ -110,7 +111,7 @@ union PicaShaderConfig {
                 bool abs_input;
                 Pica::LightingRegs::LightingLutInput type;
                 float scale;
-            } lut_d0, lut_d1, lut_fr, lut_rr, lut_rg, lut_rb;
+            } lut_d0, lut_d1, lut_sp, lut_fr, lut_rr, lut_rg, lut_rb;
         } lighting;
 
         struct {