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

data/layout.xml

@@ -2,8 +2,8 @@
 <layout>
   <flex dir="col" wrap="0" width="100%" height="100%" pad="10">
     <!-- toolbar -->
-    <plane height="50" width="100%" pad="5" dir="row">
+    <plane height="50" width="100%" pad="5" dir="row" color=".2">
-      <plane width="50" margin="0 5 0 0"></plane>
+      <plane width="50" margin="0 5 0 0" color=".6"></plane>
       <plane width="50" margin="0 5 0 0"></plane>
       <plane width="50" margin="0 5 0 0"></plane>
       <separator width="10" />
@@ -18,7 +18,7 @@
     <plane grow="1" dir="row" wrap="1" height="0">
       <plane width="200" height="100%"></plane>
       <plane width="1" grow="1" height="100%" pad="30" wrap="1">
-        <plane></plane>
+        <plane color=".2"></plane>
       </plane>
     </plane>
     <!-- status bar -->

engine/app.cpp

@@ -5,8 +5,8 @@ App App::I; // singleton
 
 void App::create()
 {
-    width = 800;
+    width = 500;
-    height = 800;
+    height = 500;
 }
 
 void App::update_layout()
@@ -99,18 +99,18 @@ void App::load_layout()
         //YGNodeStyleSetPositionType(y_root, YGPositionTypeRelative);
         while (child)
         {
-            printf("Element %s: ", child->Name());
             auto y_node = YGNodeNew();
             stack.emplace(y_node, child);
             auto attr = child->FirstAttribute();
+            std::unique_ptr<Plane> shape;
             if (strcmp("plane", child->Name()) == 0)
             {
-                auto shape = std::make_unique<Plane>();
+                shape = std::make_unique<Plane>();
-                //shape->create<5>(100.f, 100.f);
+                shape->create<5>(100.f, 100.f);
                 shape->y_node = y_node;
-                shapes_list.push_back(std::move(shape));
                 YGNodeSetContext(y_node, shape.get());
             }
+            printf("Element %s: ", child->Name());
             YGNodeStyleSetWidth(y_node, 0);
             YGNodeStyleSetWidthPercent(y_node, 100);
             YGNodeStyleSetHeight(y_node, 0);
@@ -222,6 +222,22 @@ void App::load_layout()
                     }
                     break;
                 }
+                case att::kAttribute::Color:
+                {
+                    glm::vec4 pad;
+                    int n = sscanf(attr->Value(), "%f %f %f %f", &pad.x, &pad.y, &pad.z, &pad.w);
+                    if (n == 1)
+                    {
+                        if (shape) 
+                            shape->color = glm::vec4(pad.x);
+                    }
+                    else
+                    {
+                        if (shape) 
+                            shape->color = pad;
+                    }
+                    break;
+                }
                 default:
                     break;
                 }
@@ -229,6 +245,8 @@ void App::load_layout()
             }
             int n = YGNodeGetChildCount(y_root);
             YGNodeInsertChild(y_root, y_node, n);
+            if (shape)
+                shapes_list.push_back(std::move(shape));
             child = child->NextSiblingElement();
             printf("\n");
         }
@@ -281,6 +299,25 @@ void App::init()
         "   frag = col;"
         "}";
 
+    static CONSOLE_SCREEN_BUFFER_INFO info;
+    GetConsoleScreenBufferInfo(GetStdHandle(STD_OUTPUT_HANDLE), &info);
+    // colors: http://stackoverflow.com/questions/4053837/colorizing-text-in-the-console-with-c
+    glDebugMessageCallback([](GLenum source, GLenum type, GLuint id,
+        GLenum severity, GLsizei length, const GLchar* message, const void* userParam) 
+    {
+        static std::map<GLenum, int> colors = {
+            { GL_DEBUG_SEVERITY_NOTIFICATION, 8 },
+            { GL_DEBUG_SEVERITY_LOW, 8 },
+            { GL_DEBUG_SEVERITY_MEDIUM, FOREGROUND_GREEN | FOREGROUND_INTENSITY },
+            { GL_DEBUG_SEVERITY_HIGH, FOREGROUND_RED | FOREGROUND_INTENSITY },
+        };
+        SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE), colors[severity]);
+        printf("%.*s\n", length, message);
+        FlushConsoleInputBuffer(GetStdHandle(STD_OUTPUT_HANDLE));
+        SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE), info.wAttributes);
+    }, nullptr);
+    glEnable(GL_DEBUG_OUTPUT); 
+
     load_layout();
 
     for (auto& s : shapes_list)
@@ -306,10 +343,10 @@ void App::init()
     if (!tex.load("data/uvs.jpg"))
         printf("error loading image\n");
     
-    glEnable(GL_TEXTURE);
+    glEnable(GL_TEXTURE_2D);
     glDisable(GL_DEPTH_TEST);
     glPointSize(5);
-    glLineWidth(4);
+    glLineWidth(2);
     
     //int n;
     //glGetIntegerv(GL_NUM_EXTENSIONS, &n);
@@ -383,15 +420,22 @@ void App::update(float dt)
     shader_color.use();
     shader_color.u_vec4("col", { .3f, .3f, .3f, 1 });
 
+    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
     for (auto& s : shapes_list)
     {
-        float w = YGNodeLayoutGetWidth(s->y_node);
-        float h = YGNodeLayoutGetHeight(s->y_node);
-        float x = YGNodeLayoutGetLeft(s->y_node);
-        float y = YGNodeLayoutGetTop(s->y_node);
         auto layout = *reinterpret_cast<glm::vec4*>(YGNodeGetContext(s->y_node));
-        
+        auto y_parent = YGNodeGetParent(s->y_node);
-        glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+        if (y_parent && YGNodeGetContext(y_parent))
+        {
+            auto box = *reinterpret_cast<glm::vec4*>(YGNodeGetContext(y_parent));
+            glEnable(GL_SCISSOR_TEST);
+            glScissor(box.x, height - box.y - 1 - box.w, box.z, box.w);
+        }
+        else
+        {
+            glDisable(GL_SCISSOR_TEST);
+        }
+        //glScissor(10, height - 10 - 1 - 50, 480, 50);
 
         glm::mat4 pivot = glm::translate(glm::vec3(.5f, .5f, 0.f));
         glm::mat4 scale = glm::scale(glm::vec3(layout.zw(), 1.f));
@@ -402,6 +446,12 @@ void App::update(float dt)
         //shader_uv.u_mat4("mvp", mvp);
         //plane.draw_fill();
 
+        shader_color.u_vec4("col", s->color);
+        shader_color.use();
+        shader_color.u_mat4("mvp", mvp);
+        plane.draw_fill();
+
+        shader_color.u_vec4("col", { 1, 1, 1, 1 });
         shader_color.use();
         shader_color.u_mat4("mvp", mvp);
         plane.draw_stroke();

engine/shader.cpp

@@ -62,8 +62,8 @@ bool Shader::create(std::string vertex, std::string fragment)
     glBindAttribLocation(ps, 1, "uvs");
     
     glLinkProgram(ps);
-    glGetShaderiv(ps, GL_LINK_STATUS, &status);
+    glGetProgramiv(ps, GL_LINK_STATUS, &status);
-    glGetShaderInfoLog(ps, sizeof(infolog), &infolen, infolog);
+    glGetProgramInfoLog(ps, sizeof(infolog), &infolen, infolog);
     if (infolen > 0)
         printf("LINK SHADER:\n%s", infolog);
     if (status == 0)

engine/shape.cpp

@@ -36,11 +36,13 @@ void Shape::draw_fill() const
 {
     glBindVertexArray(arrays[0]);
     glDrawElements(GL_TRIANGLES, count[0], GL_UNSIGNED_SHORT, ioff[0]);
+    glBindVertexArray(0);
 }
 void Shape::draw_stroke() const
 {
     glBindVertexArray(arrays[1]);
     glDrawElements(GL_LINES, count[1], GL_UNSIGNED_SHORT, ioff[1]);
+    glBindVertexArray(0);
 }
 
 bool Rect::create(float w, float h)

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 buffers[2]{ 0 };
-    GLuint arrays[2];
+    GLuint arrays[2]{ 0 };
-    GLuint count[2];
+    GLuint count[2]{ 0 };
-    GLvoid* ioff[2];
+    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)
     {