working symbol rendering based on point sprites

This approach ahs several advantages compared to the old approach. There
is no UNO involved anymore and we have a perfect shape defined by a
mathematical formula. No need for anti-aliasing or complex calculations
on the CPU.

Change-Id: I5018eae516de3368037c4c293d937de66f38568d

2 files changed, 58 insertions, 6 deletions

diff --git a/chart2/opengl/symbolFragmentShader.glsl b/chart2/opengl/symbolFragmentShader.glsl
index a84d83cfba48..2837f958af29 100644
--- a/chart2/opengl/symbolFragmentShader.glsl
+++ b/chart2/opengl/symbolFragmentShader.glsl
@@ -6,17 +6,70 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
-#
+
 #version 120
 
 varying vec4 fragmentColor;
+uniform int shape;
 
 void main()
 {
     vec2 p = gl_PointCoord * 2.0 - vec2(1.0); // (0,0) in the center
-    if (abs(p.x) < abs(p.y))
-        discard;
-
+    if(shape == 0)
+    {
+    }
+    else if(shape == 1) //diamon
+    {
+        if (abs(p.x) + abs(p.y) > 1)
+            discard;
+    }
+    else if(shape == 2) // arrow
+    {
+        if(p.y < 0 && (abs(p.x) + abs(p.y)) > 1)
+            discard;
+        else if(p.y > 0 && abs(p.x) > 0.5)
+            discard;
+    }
+    else if(shape == 3) //arrow up
+    {
+        if(p.y > 0 && (abs(p.x) + abs(p.y)) > 1)
+            discard;
+        else if(p.y < 0 && abs(p.x) > 0.5)
+            discard;
+    }
+    else if(shape == 4)
+    {
+        if(p.x > 0 && (abs(p.x) + abs(p.y)) > 1)
+            discard;
+        else if(p.x < 0 && abs(p.y) > 0.5)
+            discard;
+    }
+    else if(shape == 5)
+    {
+        if(p.x < 0 && (abs(p.x) + abs(p.y)) > 1)
+            discard;
+        else if(p.x > 0 && abs(p.y) > 0.5)
+            discard;
+    }
+    else if(shape == 6)
+    {
+        if(abs(p.x) < abs(p.y))
+            discard;
+    }
+    else if(shape == 7)
+    {
+        if(abs(p.y) < abs(p.x))
+            discard;
+    }
+    else if(shape == 8)
+    {
+        if(dot(p.x, p.y) > 1)
+            discard;
+    }
+    else if(shape == 9)
+    {
+    }
+    
     gl_FragColor = fragmentColor;
 }
 
diff --git a/chart2/opengl/symbolVertexShader.glsl b/chart2/opengl/symbolVertexShader.glsl
index e1bbec9bc202..3cf9f41ef21b 100644
--- a/chart2/opengl/symbolVertexShader.glsl
+++ b/chart2/opengl/symbolVertexShader.glsl
@@ -16,9 +16,8 @@ varying vec4 fragmentColor;
 
 void main()
 {
-    gl_Position =  MVP * vec4(vPosition, 1);
+    gl_Position = MVP * vec4(vPosition, 1);
     fragmentColor = vColor;
-    gl_PointSize = 10.0;
 }
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */