Render eye view with off-center projection to better match visible area

[libs/vr.git] / source / oculusriftcombiner.cpp

diff --git a/source/oculusriftcombiner.cpp b/source/oculusriftcombiner.cpp
index 771f3b82a3cd7df48f48854b10e7b786c931bc72..3ebbcc88914aea5d070bf265c5cd27556cf5274c 100644 (file)
--- a/source/oculusriftcombiner.cpp
+++ b/source/oculusriftcombiner.cpp
@@ -21,21 +21,24 @@ const char vs_source[] =
 const char fs_source[] =
        "uniform sampler2D texture;\n"
        "uniform vec4 distortion;\n"
+       "uniform vec4 chromatic;\n"
+       "uniform vec2 lens_center;\n"
        "uniform vec2 eye_center;\n"
        "uniform vec3 scale;\n"
        "varying vec2 texcoord;\n"
-       "vec2 distort(vec2 coord)\n"
-       "{\n"
-       "       float r_sq = dot(coord, coord);\n"
-       "       return coord*dot(distortion, vec4(1.0, r_sq, r_sq*r_sq, r_sq*r_sq*r_sq));\n"
-       "}\n"
        "void main()\n"
        "{\n"
-       "       vec2 dtc = (distort(texcoord)-eye_center)/(scale.xy*scale.z)+0.5;\n"
+       "       float r_sq = dot(texcoord, texcoord);\n"
+       "       float f = dot(distortion, vec4(1.0, r_sq, r_sq*r_sq, r_sq*r_sq*r_sq));\n"
+       "       vec2 dtc = (texcoord*f-eye_center)/(scale.xy*scale.z)+lens_center;\n"
        "       if(dtc.x<0.0 || dtc.y<0.0 || dtc.x>1.0 || dtc.y>1.0)\n"
        "               gl_FragColor = vec4(0.0);\n"
        "       else\n"
-       "               gl_FragColor = texture2D(texture, dtc);\n"
+       "       {\n"
+       "               vec2 red_dtc = (texcoord*f*(chromatic[0]+chromatic[1]*r_sq)-eye_center)/(scale.xy*scale.z)+lens_center;\n"
+       "               vec2 blue_dtc = (texcoord*f*(chromatic[2]+chromatic[3]*r_sq)-eye_center)/(scale.xy*scale.z)+lens_center;\n"
+       "               gl_FragColor = vec4(texture2D(texture, red_dtc).r, texture2D(texture, dtc).g, texture2D(texture, blue_dtc).b, 1.0);\n"
+       "       }\n"
        "}\n";
 
 }
@@ -59,6 +62,11 @@ OculusRiftCombiner::OculusRiftCombiner():
        right_shdata.uniform("texture", 0);
        right_shdata.uniform("offset", 0.5f);
 
+       chromatic[0] = 1.0f;
+       chromatic[1] = 0.0f;
+       chromatic[2] = 1.0f;
+       chromatic[3] = 0.0f;
+
        // This will also call update_parameters
        set_distortion(1.0f, 0.22f, 0.24f);
 
@@ -99,6 +107,22 @@ void OculusRiftCombiner::set_distortion(float d0, float d1, float d2, float d3)
        update_parameters();
 }
 
+void OculusRiftCombiner::set_red_aberration(float c0, float c1)
+{
+       chromatic[0] = c0;
+       chromatic[1] = c1;
+
+       update_parameters();
+}
+
+void OculusRiftCombiner::set_blue_aberration(float c2, float c3)
+{
+       chromatic[2] = c2;
+       chromatic[3] = c3;
+
+       update_parameters();
+}
+
 void OculusRiftCombiner::set_fill_factor(float f)
 {
        fill_factor = f;
@@ -108,7 +132,9 @@ void OculusRiftCombiner::set_fill_factor(float f)
 void OculusRiftCombiner::update_parameters()
 {
        left_shdata.uniform4("distortion", distortion);
+       left_shdata.uniform4("chromatic", chromatic);
        right_shdata.uniform4("distortion", distortion);
+       right_shdata.uniform4("chromatic", chromatic);
 
        // Set lens center positions, in output texture coordinates
        left_shdata.uniform("lens_center", 1.0f-lens_separation, 0.5);
@@ -122,7 +148,7 @@ void OculusRiftCombiner::update_parameters()
 
        /* Determine the necessary scaling factor to avoid quality degradation in
        the center of the screen. */
-       float horiz_oversize = distort((fill_factor-lens_separation)*2)-eye_offset;
+       float horiz_oversize = distort((fill_factor-lens_separation)*2)/((fill_factor-lens_separation)*2)-eye_offset;
        float vert_oversize = distort(1.25f*fill_factor)/(1.25f*fill_factor);
        oversize = min(horiz_oversize, vert_oversize);
 
@@ -130,6 +156,7 @@ void OculusRiftCombiner::update_parameters()
        right_shdata.uniform("scale", 2.0f, 2.5f, oversize);
 
        fov = Geometry::atan(oversize*0.625f/view_distance)*2.0f;
+       frustum_skew = lens_separation*2-1;
 }
 
 float OculusRiftCombiner::distort(float r) const