ENH: 3dbed: support rendering extruder area with different color

JIRA: STUDIO-7494
Change-Id: I717999e8b7ab1d7d350299b412a3a270c6ba7a9e
(cherry picked from commit 62b1d00d1fd6675fd067b76778d6a577dfae0c24)

resources/shaders/110/hotbed.fs

@@ -0,0 +1,43 @@
+#version 110
+
+const vec3 ZERO = vec3(0.0, 0.0, 0.0);
+const vec3 WHITE = vec3(1.0, 1.0, 1.0);
+struct PrintVolumeDetection
+{
+	// 0 = rectangle, 1 = circle, 2 = custom, 3 = invalid
+	int type;
+    // type = 0 (rectangle):
+    // x = min.x, y = min.y, z = max.x, w = max.y
+    // type = 1 (circle):
+    // x = center.x, y = center.y, z = radius
+	vec4 xy_data;
+    // x = min z, y = max z
+	vec2 z_data;
+};
+
+uniform vec4 uniform_color;
+uniform float emission_factor;
+uniform PrintVolumeDetection print_volume;
+// x = diffuse, y = specular;
+varying vec2 intensity;
+varying vec4 world_pos;
+void main()
+{
+    vec3  color = uniform_color.rgb;
+    float alpha = uniform_color.a;
+	// if the fragment is outside the print volume -> use darker color
+    vec3 pv_check_min = ZERO;
+    vec3 pv_check_max = ZERO;
+    if (print_volume.type == 0) {// rectangle
+        pv_check_min = world_pos.xyz - vec3(print_volume.xy_data.x, print_volume.xy_data.y, print_volume.z_data.x);
+        pv_check_max = world_pos.xyz - vec3(print_volume.xy_data.z, print_volume.xy_data.w, print_volume.z_data.y);
+    }
+    else if (print_volume.type == 1) {// circle
+        float delta_radius = print_volume.xy_data.z - distance(world_pos.xy, print_volume.xy_data.xy);
+        pv_check_min = vec3(delta_radius, 0.0, world_pos.z - print_volume.z_data.x);
+        pv_check_max = vec3(0.0, 0.0, world_pos.z - print_volume.z_data.y);
+    }
+    color = (any(lessThan(pv_check_min, ZERO)) || any(greaterThan(pv_check_max, ZERO))) ? mix(color, WHITE, 0.3333) : color;
+	//gl_FragColor = vec4(vec3(intensity.y) + color * intensity.x, alpha);
+	gl_FragColor = vec4(vec3(intensity.y) + color * (intensity.x + emission_factor), alpha);
+}

resources/shaders/110/hotbed.vs

@@ -0,0 +1,47 @@
+#version 110
+
+#define INTENSITY_CORRECTION 0.6
+
+// normalized values for (-0.6/1.31, 0.6/1.31, 1./1.31)
+const vec3 LIGHT_TOP_DIR = vec3(-0.4574957, 0.4574957, 0.7624929);
+#define LIGHT_TOP_DIFFUSE    (0.8 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SPECULAR   (0.125 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SHININESS  20.0
+
+// normalized values for (1./1.43, 0.2/1.43, 1./1.43)
+const vec3 LIGHT_FRONT_DIR = vec3(0.6985074, 0.1397015, 0.6985074);
+#define LIGHT_FRONT_DIFFUSE  (0.3 * INTENSITY_CORRECTION)
+
+#define INTENSITY_AMBIENT    0.3
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+uniform mat3 view_normal_matrix;
+uniform mat4 volume_world_matrix;
+
+attribute vec3 v_position;
+attribute vec3 v_normal;
+
+// x = tainted, y = specular;
+varying vec2 intensity;
+varying vec4 world_pos;
+void main()
+{
+    // First transform the normal into camera space and normalize the result.
+    vec3 normal = normalize(view_normal_matrix * v_normal);
+
+    // Compute the cos of the angle between the normal and lights direction. The light is directional so the direction is constant for every vertex.
+    // Since these two are normalized the cosine is the dot product. We also need to clamp the result to the [0,1] range.
+    float NdotL = max(dot(normal, LIGHT_TOP_DIR), 0.0);
+
+    intensity.x = INTENSITY_AMBIENT + NdotL * LIGHT_TOP_DIFFUSE;
+    world_pos = volume_world_matrix * vec4(v_position, 1.0);
+    vec4 position = view_model_matrix * vec4(v_position, 1.0);
+    intensity.y = LIGHT_TOP_SPECULAR * pow(max(dot(-normalize(position.xyz), reflect(-LIGHT_TOP_DIR, normal)), 0.0), LIGHT_TOP_SHININESS);
+
+    // Perform the same lighting calculation for the 2nd light source (no specular applied).
+    NdotL = max(dot(normal, LIGHT_FRONT_DIR), 0.0);
+    intensity.x += NdotL * LIGHT_FRONT_DIFFUSE;
+
+    gl_Position = projection_matrix * position;
+}