HDR: Add support for glTF emissive objects

Shaders/HDR/model_pbr_transparent.frag

@@ -28,7 +28,7 @@ vec3 eotf_inverse_sRGB(vec3 srgb);
 // shading_transparent.glsl
 vec3 eval_lights_transparent(
     vec3 base_color, float metallic, float roughness, float occlusion,
-    vec3 P, vec3 N, vec3 V, vec2 uv, vec4 ap,
+    vec3 emissive, vec3 P, vec3 N, vec3 V, vec2 uv, vec4 ap,
     mat4 view_matrix_inverse);
 // normalmap.glsl
 vec3 perturb_normal(vec3 N, vec3 V, vec2 texcoord);
@@ -54,7 +54,7 @@ void main()
     N = perturb_normal(N, fs_in.view_vector, fs_in.texcoord);
 
     vec3 color = eval_lights_transparent(
-        base_color.rgb, metallic, roughness, occlusion,
+        base_color.rgb, metallic, roughness, occlusion, emissive,
         fs_in.view_vector, N, V, uv, fs_in.ap_color, osg_ViewMatrixInverse);
 
     fragColor = vec4(color, base_color.a);

Shaders/HDR/model_transparent.frag

@@ -21,7 +21,7 @@ vec3 eotf_inverse_sRGB(vec3 srgb);
 // shading_transparent.glsl
 vec3 eval_lights_transparent(
     vec3 base_color, float metallic, float roughness, float occlusion,
-    vec3 P, vec3 N, vec3 V, vec2 uv, vec4 ap,
+    vec3 emissive, vec3 P, vec3 N, vec3 V, vec2 uv, vec4 ap,
     mat4 view_matrix_inverse);
 
 void main()
@@ -35,7 +35,7 @@ void main()
     vec2 uv = (gl_FragCoord.xy - fg_Viewport.xy) / fg_Viewport.zw;
 
     vec3 color = eval_lights_transparent(
-        base_color, TRANSPARENT_METALLIC, TRANSPARENT_ROUGHNESS, 1.0,
+        base_color, TRANSPARENT_METALLIC, TRANSPARENT_ROUGHNESS, 1.0, vec3(0.0),
         vP, N, V, uv, ap_color, osg_ViewMatrixInverse);
 
     fragColor = vec4(color, alpha);

Shaders/HDR/shading_opaque.frag

@@ -18,7 +18,7 @@ void gbuffer_unpack(in vec2 texcoord,
 // shading_opaque.glsl
 vec3 eval_lights(
     vec3 base_color, float metallic, float roughness, float occlusion,
-    vec3 P, vec3 N, vec3 V, vec2 uv,
+    vec3 emissive, vec3 P, vec3 N, vec3 V, vec2 uv,
     mat4 view_matrix_inverse, mat4 projection_matrix);
 // pos_from_depth.glsl
 vec3 get_view_space_from_depth(vec2 uv);
@@ -36,6 +36,6 @@ void main()
 
     fragColor = eval_lights(
         base_color, metallic, roughness, occlusion,
-        P, N, V, texcoord,
+        emissive, P, N, V, texcoord,
         fg_ViewMatrixInverse, fg_ProjectionMatrix);
 }

Shaders/HDR/shading_opaque.glsl

@@ -29,7 +29,7 @@ vec3 apply_exposure(vec3 color);
 
 vec3 eval_lights(
     vec3 base_color, float metallic, float roughness, float occlusion,
-    vec3 P, vec3 N, vec3 V, vec2 uv,
+    vec3 emissive, vec3 P, vec3 N, vec3 V, vec2 uv,
     mat4 view_matrix_inverse, mat4 projection_matrix)
 {
     vec3 f0 = f0_from_pbr(base_color, metallic);
@@ -59,6 +59,9 @@ vec3 eval_lights(
         base_color, metallic, roughness, f0,
         ao, ws_N, ws_refl, NdotV);
 
+    // Add emissive contribution
+    color += emissive;
+
     // Add aerial perspective
     color = add_aerial_perspective(color, uv, length(P));
 

Shaders/HDR/shading_transparent.glsl

@@ -26,7 +26,7 @@ vec3 apply_exposure(vec3 color);
 
 vec3 eval_lights_transparent(
     vec3 base_color, float metallic, float roughness, float occlusion,
-    vec3 P, vec3 N, vec3 V, vec2 uv, vec4 ap,
+    vec3 emissive, vec3 P, vec3 N, vec3 V, vec2 uv, vec4 ap,
     mat4 view_matrix_inverse)
 {
     vec3 f0 = f0_from_pbr(base_color, metallic);
@@ -53,6 +53,9 @@ vec3 eval_lights_transparent(
         base_color, metallic, roughness, f0,
         occlusion, ws_N, ws_refl, NdotV);
 
+    // Add emissive contribution
+    color += emissive;
+
     // Add aerial perspective
     color = mix_aerial_perspective(color, ap);