HDRI Local Preview (#953)

* #926 WIP - HDRI import prototype v0

* #926 WIP -- add OpenEXR to autobuild.xml

* #926 WIP -- Add OpenEXR cmake

* #926 WIP -- Attempt at using OpenEXR autobuild package and don't hard code .exr file to load

* #926 Unmangle autobuild.xml and get dll's in the right place (thanks, Caladbolg!)

* implement mac shared libs plumbing for OpenEXR for secondlife/viewer#926

* Fix Xcode/clang compile error regarding new[]/delete[] mismatch

* #926 HDRI Preview finishing touches.

- Full ACES when HDRI is enabled
- Fix for probes getting stuck paused
- Add exposure and rotation controls

---------

Co-authored-by: Brad Linden <brad@lindenlab.com>

3 files changed, 32 insertions, 2 deletions

diff --git a/indra/newview/app_settings/shaders/class1/deferred/postDeferredGammaCorrect.glsl b/indra/newview/app_settings/shaders/class1/deferred/postDeferredGammaCorrect.glsl
index 3443785e1a..d89377326e 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/postDeferredGammaCorrect.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/postDeferredGammaCorrect.glsl
@@ -97,6 +97,7 @@ vec3 toneMapACES_Hill(vec3 color)
 
 uniform float exposure;
 uniform float gamma;
+uniform float aces_mix;
 
 vec3 toneMap(vec3 color)
 {
@@ -106,7 +107,7 @@ vec3 toneMap(vec3 color)
     color *= exposure * exp_scale;
 
     // mix ACES and Linear here as a compromise to avoid over-darkening legacy content
-    color = mix(toneMapACES_Hill(color), color, 0.3);
+    color = mix(toneMapACES_Hill(color), color, aces_mix);
 #endif
 
     return color;
diff --git a/indra/newview/app_settings/shaders/class1/deferred/skyF.glsl b/indra/newview/app_settings/shaders/class1/deferred/skyF.glsl
index 9d9ba49d82..cc5280d929 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/skyF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/skyF.glsl
@@ -27,6 +27,13 @@
 in vec3 vary_HazeColor;
 in float vary_LightNormPosDot;
 
+#ifdef HAS_HDRI
+in vec3 vary_position;
+uniform float sky_hdr_scale;
+uniform mat3 env_mat;
+uniform sampler2D environmentMap;
+#endif
+
 uniform sampler2D rainbow_map;
 uniform sampler2D halo_map;
 
@@ -37,6 +44,9 @@ uniform float ice_level;
 out vec4 frag_data[4];
 
 vec3 srgb_to_linear(vec3 c);
+vec3 linear_to_srgb(vec3 c);
+
+#define PI 3.14159265
 
 /////////////////////////////////////////////////////////////////////////
 // The fragment shader for the sky
@@ -71,6 +81,14 @@ vec3 halo22(float d)
 
 void main()
 {
+#ifdef HAS_HDRI
+    vec3 pos = normalize(vary_position);
+    pos = env_mat * pos;
+    vec2 texCoord = vec2(atan(pos.z, pos.x) + PI, acos(pos.y)) / vec2(2.0 * PI, PI);
+    vec3 color = textureLod(environmentMap, texCoord.xy, 0).rgb * sky_hdr_scale;
+    color = min(color, vec3(8192*8192*16));
+#else
+
     // Potential Fill-rate optimization.  Add cloud calculation 
     // back in and output alpha of 0 (so that alpha culling kills 
     // the fragment) if the sky wouldn't show up because the clouds 
@@ -86,9 +104,12 @@ void main()
     color.rgb *= 2.;
     color.rgb = clamp(color.rgb, vec3(0), vec3(5));
 
+#endif
+
     frag_data[0] = vec4(0);
     frag_data[1] = vec4(0);
-    frag_data[2] = vec4(0.0,0.0,0.0,GBUFFER_FLAG_SKIP_ATMOS); //1.0 in norm.w masks off fog
+    frag_data[2] = vec4(0.0,0.0,0.0,GBUFFER_FLAG_SKIP_ATMOS);
     frag_data[3] = vec4(color.rgb, 1.0);
+
 }
 
diff --git a/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl b/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl
index 17ce2dee5b..bbe9a5a838 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl
@@ -35,6 +35,10 @@ in vec3 position;
 out vec3 vary_HazeColor;
 out float vary_LightNormPosDot;
 
+#ifdef HAS_HDRI
+out vec3 vary_position;
+#endif
+
 // Inputs
 uniform vec3 camPosLocal;
 
@@ -72,6 +76,10 @@ void main()
     // Get relative position
     vec3 rel_pos = position.xyz - camPosLocal.xyz + vec3(0, 50, 0);
 
+#ifdef HAS_HDRI
+    vary_position = rel_pos;
+#endif
+
     // Adj position vector to clamp altitude
     if (rel_pos.y > 0.)
     {