added color attribute and scissor clipping. Added debug callback to OpenGL messages

engine/shape.hpp

@@ -7,7 +7,8 @@ namespace att
         Height, MinHeight, MaxHeight, 
         Divisions, InnerRadius, OuterRadius,
         Grow, Shrink, FlexDir, FlexWrap, 
-        Padding, Margin
+        Padding, Margin,
+        Color
     };
 
     struct AttributeBase 
@@ -47,7 +48,8 @@ namespace att
         { "dir", kAttribute::FlexDir },
         { "wrap", kAttribute::FlexWrap },
         { "pad", kAttribute::Padding },
-        { "margin", kAttribute::Margin},
+        { "margin", kAttribute::Margin },
+        { "color", kAttribute::Color },
     };
     constexpr int map_size = sizeof(map) / sizeof(typemap) - 1;
     constexpr bool same(const char* a, const char* b)
@@ -88,6 +90,7 @@ namespace att
     DECLARE_ATTRIBUTE(FlexWrap, int);
     DECLARE_ATTRIBUTE(Padding, glm::vec4);
     DECLARE_ATTRIBUTE(Margin, glm::vec4);
+    DECLARE_ATTRIBUTE(Color, glm::vec4);
 
 #undef DECLARE_ATTRIBUTE
 }
@@ -95,19 +98,24 @@ namespace att
 class Shape
 {
 protected:
-    GLuint buffers[2];
-    GLuint arrays[2];
-    GLuint count[2];
-    GLvoid* ioff[2];
+    GLuint buffers[2]{ 0 };
+    GLuint arrays[2]{ 0 };
+    GLuint count[2]{ 0 };
+    GLvoid* ioff[2]{ 0 };
     struct vertex_t { glm::vec4 pos; glm::vec2 uvs; };
 public:
     YGNodeRef y_node;
-    float x, y;
+    glm::vec4 color;
     att::AttrubutesMap attribs;
     bool create_buffers(GLvoid* idx, GLvoid* vertices, int isize, int vsize);
     void draw_fill() const;
     void draw_stroke() const;
     virtual bool create_attrib() { return true; };
+    ~Shape()
+    {
+        glDeleteBuffers(2, buffers);
+        glDeleteVertexArrays(2, arrays);
+    }
 protected:
     glm::vec2 quad_mid_point(glm::vec2 a, glm::vec2 b, glm::vec2 c, glm::vec2 d)
     {