Added RGB cardinal-axis lines and brighter lines every 10 units. #56

source/OpenGL/GLSL/grid.vert

@@ -1,19 +1,18 @@
 #version 420 core
 
 layout (location = 0) in vec3 VertexPosition;
+layout (location = 4) in vec4 VertexColour;
 
 layout(shared) uniform ViewProperties
 {
     mat4 view;
     mat4 projection;
 } viewProperties;
 
-uniform vec4 colour;
-
 out vec4 FragmentColour;
 
 void main()
 {
     gl_Position    = viewProperties.projection * viewProperties.view * vec4(VertexPosition, 1.0);
-	FragmentColour = colour;
+	FragmentColour = VertexColour;
 }

source/OpenGL/GridRenderer.cpp

@@ -4,22 +4,46 @@ namespace OpenGL
 {
     GridRenderer::GridRenderer() noexcept
         : m_line_points{}
-        , m_colour{1.f, 1.f, 1.f, 0.7f}
         , m_grid_shader{"grid"}
         , m_line_VAO{}
         , m_line_VBO{}
     {
-        constexpr int Count = 1000;
-        constexpr int Size  = 100; // #Todo Should be camera z-far
-        m_line_points.reserve(Count * 8);
+        constexpr int Size                        = 1000; // Used for the size and number of lines to draw.
+        constexpr float transparency              = 0.7f;
+        constexpr glm::vec4 primary_line_colour   = glm::vec4{0.5f, 0.5f, 0.5f, transparency};
+        constexpr glm::vec4 secondary_line_colour = glm::vec4{0.2f, 0.2f, 0.2f, transparency};
+        constexpr glm::vec4 red                   = glm::vec4{1.f, 0.f, 0.f, transparency};
+        constexpr glm::vec4 green                 = glm::vec4{0.f, 1.f, 0.f, transparency};
+        constexpr glm::vec4 blue                  = glm::vec4{0.f, 0.f, 1.f, transparency};
 
-        // XZ-plane
-        for (auto i = -Count; i <= Count; i++)
+        m_line_points.reserve((Size * 8) + 6);
+
+        { // Cardinal axis lines
+            m_line_points.push_back({glm::vec3{-Size, 0.f, 0.f}, red});
+            m_line_points.push_back({glm::vec3{Size, 0.f, 0.f},  red});
+            m_line_points.push_back({glm::vec3{0.f, -Size, 0.f}, green});
+            m_line_points.push_back({glm::vec3{0.f, Size, 0.f},  green});
+            m_line_points.push_back({glm::vec3{0.f, 0.f, -Size}, blue});
+            m_line_points.push_back({glm::vec3{0.f, 0.f, Size},  blue});
+        }
+
+        // XZ-plane lines
+        for (auto i = -Size; i <= Size; i++)
         {
-            m_line_points.push_back({glm::vec3{-Size, 0.f, i}});
-            m_line_points.push_back({glm::vec3{Size, 0.f, i}});
-            m_line_points.push_back({glm::vec3{i, 0.f, Size}});
-            m_line_points.push_back({glm::vec3{i, 0.f, -Size}});
+            if (i % 10 == 0)
+            {
+                m_line_points.push_back({glm::vec3{-Size, 0.f, i}, primary_line_colour});
+                m_line_points.push_back({glm::vec3{Size, 0.f, i }, primary_line_colour});
+                m_line_points.push_back({glm::vec3{i, 0.f, Size }, primary_line_colour});
+                m_line_points.push_back({glm::vec3{i, 0.f, -Size}, primary_line_colour});
+            }
+            else if (i != 0) // Ignore 0, cardinal axis lines are added above.
+            {
+                m_line_points.push_back({glm::vec3{-Size, 0.f, i}, secondary_line_colour});
+                m_line_points.push_back({glm::vec3{Size, 0.f, i }, secondary_line_colour});
+                m_line_points.push_back({glm::vec3{i, 0.f, Size }, secondary_line_colour});
+                m_line_points.push_back({glm::vec3{i, 0.f, -Size}, secondary_line_colour});
+            }
         }
 
         m_line_VAO.bind();
@@ -30,7 +54,6 @@ namespace OpenGL
         if (!m_line_points.empty())
         {
             m_grid_shader.use();
-            m_grid_shader.set_uniform("colour", m_colour);
             toggle_cull_face(false);
             set_depth_test(true);
             set_depth_test_type(DepthTestType::Less);

source/OpenGL/GridRenderer.hpp

@@ -13,12 +13,12 @@ namespace OpenGL
     {
         struct GridVert
         {
-            constexpr inline static std::array<VertexAttribute, 1> Attributes = { VertexAttribute::Position3D };
+            constexpr inline static std::array<VertexAttribute, 2> Attributes = { VertexAttribute::Position3D, VertexAttribute::ColourRGBA };
             glm::vec3 m_position = glm::vec3{0.f};
+            glm::vec4 m_colour   = glm::vec4{1.f};
         };
 
         std::vector<GridVert> m_line_points;
-        glm::vec4 m_colour;
         Shader m_grid_shader;
         VAO m_line_VAO;
         VBO m_line_VBO;