ES2 shader support for surface

Task-number: QTRD-2290

Change-Id: I52a7fbd8d72e6cd4f73dd3072103cdbf518df321
Change-Id: I52a7fbd8d72e6cd4f73dd3072103cdbf518df321
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@digia.com>

4 files changed, 39 insertions, 32 deletions

diff --git a/src/datavisualization/engine/shaders/surface.vert b/src/datavisualization/engine/shaders/surface.vert
index cbfb7569..a44d413b 100644
--- a/src/datavisualization/engine/shaders/surface.vert
+++ b/src/datavisualization/engine/shaders/surface.vert
@@ -1,5 +1,3 @@
-#version 120
-
 attribute highp vec3 vertexPosition_mdl;
 attribute highp vec2 vertexUV;
 attribute highp vec3 vertexNormal_mdl;
diff --git a/src/datavisualization/engine/shaders/surfaceGrid.frag b/src/datavisualization/engine/shaders/surfaceGrid.frag
index 20b923fb..1658b316 100644
--- a/src/datavisualization/engine/shaders/surfaceGrid.frag
+++ b/src/datavisualization/engine/shaders/surfaceGrid.frag
@@ -1,14 +1,4 @@
-varying highp vec2 UV;
-varying highp vec2 coords_mdl;
-varying highp vec3 position_wrld;
-varying highp vec3 normal_cmr;
-varying highp vec3 eyeDirection_cmr;
-varying highp vec3 lightDirection_cmr;
-
-uniform highp vec3 lightPosition_wrld;
 uniform highp vec3 color_mdl;
-uniform highp float lightStrength;
-uniform highp float ambientStrength;
 
 void main() {
     gl_FragColor.rgb = color_mdl;
diff --git a/src/datavisualization/engine/shaders/surfaceGrid.vert b/src/datavisualization/engine/shaders/surfaceGrid.vert
index efb40862..5582d633 100644
--- a/src/datavisualization/engine/shaders/surfaceGrid.vert
+++ b/src/datavisualization/engine/shaders/surfaceGrid.vert
@@ -1,26 +1,6 @@
 attribute highp vec3 vertexPosition_mdl;
-attribute highp vec2 vertexUV;
-attribute highp vec3 vertexNormal_mdl;
-
 uniform highp mat4 MVP;
-uniform highp mat4 V;
-uniform highp mat4 M;
-uniform highp mat4 itM;
-uniform highp vec3 lightPosition_wrld;
-
-varying highp vec3 position_wrld;
-varying highp vec3 normal_cmr;
-varying highp vec3 eyeDirection_cmr;
-varying highp vec3 lightDirection_cmr;
-varying highp vec2 coords_mdl;
 
 void main() {
     gl_Position = MVP * vec4(vertexPosition_mdl, 1.0);
-    coords_mdl = vertexPosition_mdl.xy;
-    position_wrld = (M * vec4(vertexPosition_mdl, 1.0)).xyz;
-    vec3 vertexPosition_cmr = (V * M * vec4(vertexPosition_mdl, 1.0)).xyz;
-    eyeDirection_cmr = vec3(0.0, 0.0, 0.0) - vertexPosition_cmr;
-    vec3 lightPosition_cmr = (V * vec4(lightPosition_wrld, 1.0)).xyz;
-    lightDirection_cmr = lightPosition_cmr + eyeDirection_cmr;
-    normal_cmr = (V * itM * vec4(vertexNormal_mdl, 0.0)).xyz;
 }
diff --git a/src/datavisualization/engine/shaders/surface_ES2.frag b/src/datavisualization/engine/shaders/surface_ES2.frag
new file mode 100644
index 00000000..a9aec528
--- /dev/null
+++ b/src/datavisualization/engine/shaders/surface_ES2.frag
@@ -0,0 +1,39 @@
+varying highp vec2 UV;
+varying highp vec3 coords_mdl;
+varying highp vec3 position_wrld;
+varying highp vec3 normal_cmr;
+varying highp vec3 eyeDirection_cmr;
+varying highp vec3 lightDirection_cmr;
+
+uniform sampler2D textureSampler;
+uniform highp vec3 lightPosition_wrld;
+uniform highp float lightStrength;
+uniform highp float ambientStrength;
+
+void main() {
+    highp vec2 gradientUV = vec2(0.5, (coords_mdl.y + 1.0) / 2.0);
+    highp vec3 materialDiffuseColor = texture2D(textureSampler, gradientUV).xyz;
+    highp vec3 materialAmbientColor = vec3(ambientStrength, ambientStrength, ambientStrength) * materialDiffuseColor;
+    highp vec3 materialSpecularColor = vec3(1.0, 1.0, 1.0);
+
+    highp float distance = length(lightPosition_wrld - position_wrld);
+
+    highp vec3 n = normalize(normal_cmr);
+    highp vec3 l = normalize(lightDirection_cmr);
+    highp float cosTheta = dot(n, l);
+    if (cosTheta < 0.0) cosTheta = 0.0;
+    else if (cosTheta > 1.0) cosTheta = 1.0;
+
+    highp vec3 E = normalize(eyeDirection_cmr);
+    highp vec3 R = reflect(-l, n);
+    highp float cosAlpha = dot(E, R);
+    if (cosAlpha < 0.0) cosAlpha = 0.0;
+    else if (cosAlpha > 1.0) cosAlpha = 1.0;
+
+    gl_FragColor.rgb =
+        materialAmbientColor +
+        materialDiffuseColor * lightStrength * cosTheta * cosTheta / distance +
+        materialSpecularColor * lightStrength * cosAlpha * cosAlpha * cosAlpha * cosAlpha * cosAlpha * cosAlpha * cosAlpha * cosAlpha * cosAlpha * cosAlpha / distance;
+    gl_FragColor.a = 1.0;
+}
+