Use Mesh class in Darken Center effect

Author: kblaschke

src/libprojectM/MilkdropPreset/DarkenCenter.cpp

@@ -4,41 +4,35 @@ namespace libprojectM {
 namespace MilkdropPreset {
 
 DarkenCenter::DarkenCenter(PresetState& presetState)
-    : RenderItem()
-    , m_presetState(presetState)
+    : m_presetState(presetState)
+    , m_mesh(Renderer::VertexBufferUsage::StaticDraw, true, false)
 {
-    RenderItem::Init();
-}
-
-void DarkenCenter::InitVertexAttrib()
-{
-    glEnableVertexAttribArray(0);
-    glEnableVertexAttribArray(1);
-
-    glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(ColoredPoint), nullptr);                                            // points
-    glVertexAttribPointer(1, 4, GL_FLOAT, GL_FALSE, sizeof(ColoredPoint), reinterpret_cast<void*>(offsetof(ColoredPoint, r))); // colors
+    m_mesh.SetRenderPrimitiveType(Renderer::Mesh::PrimitiveType::TriangleFan);
+    m_mesh.SetVertexCount(6);
+    m_mesh.Colors().Set({{0.0f, 0.0f, 0.0f, 3.0f / 32.0f},
+                         {0.0f, 0.0f, 0.0f, 0.0f},
+                         {0.0f, 0.0f, 0.0f, 0.0f},
+                         {0.0f, 0.0f, 0.0f, 0.0f},
+                         {0.0f, 0.0f, 0.0f, 0.0f},
+                         {0.0f, 0.0f, 0.0f, 0.0f}});
+    m_mesh.Update();
 }
 
 void DarkenCenter::Draw()
 {
-    glBindVertexArray(m_vaoID);
-
     if (m_presetState.renderContext.aspectY != m_aspectY)
     {
         m_aspectY = m_presetState.renderContext.aspectY;
 
         // Update mesh with new aspect ratio if needed
-        float const halfSize = 0.05f;
-        std::array<ColoredPoint, 6> vertices = {{{0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 3.0f / 32.0f},
-                                                 {0.0f - halfSize * m_aspectY, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f},
-                                                 {0.0f, 0.0f - halfSize, 0.0f, 0.0f, 0.0f, 0.0f},
-                                                 {0.0f + halfSize * m_aspectY, 0.0, 0.0f, 0.0f, 0.0f, 0.0f},
-                                                 {0.0f, 0.0f + halfSize, 0.0f, 0.0f, 0.0f, 0.0f},
-                                                 {0.0f - halfSize * m_aspectY, 0.0, 0.0f, 0.0f, 0.0f, 0.0f}}};
-
-        glBindBuffer(GL_ARRAY_BUFFER, m_vboID);
-        glBufferData(GL_ARRAY_BUFFER, sizeof(ColoredPoint) * vertices.size(), vertices.data(), GL_STATIC_DRAW);
-        glBindBuffer(GL_ARRAY_BUFFER, 0);
+        constexpr float halfSize = 0.05f;
+        m_mesh.Vertices().Set({{0.0f, 0.0f},
+                               {0.0f - halfSize * m_aspectY, 0.0f},
+                               {0.0f, 0.0f - halfSize},
+                               {0.0f + halfSize * m_aspectY, 0.0f},
+                               {0.0f, 0.0f + halfSize},
+                               {0.0f - halfSize * m_aspectY, 0.0f}});
+        m_mesh.Update();
     }
 
     glEnable(GL_BLEND);
@@ -48,10 +42,10 @@ void DarkenCenter::Draw()
     shader->Bind();
     shader->SetUniformMat4x4("vertex_transformation", PresetState::orthogonalProjection);
 
-    glDrawArrays(GL_TRIANGLE_FAN, 0, 6);
+    m_mesh.Draw();
 
     glDisable(GL_BLEND);
-    glBindVertexArray(0);
+    Renderer::Mesh::Unbind();
     Renderer::Shader::Unbind();
 }
 

src/libprojectM/MilkdropPreset/DarkenCenter.hpp

@@ -2,31 +2,30 @@
 
 #include "PresetState.hpp"
 
-#include <Renderer/RenderItem.hpp>
+#include <Renderer/Mesh.hpp>
 
 namespace libprojectM {
 namespace MilkdropPreset {
 
 /**
  * @brief Darkens the screen center a bit on each frame.
  */
-class DarkenCenter : public Renderer::RenderItem
+class DarkenCenter
 {
 public:
     DarkenCenter() = delete;
 
     explicit DarkenCenter(PresetState& presetState);
 
-    void InitVertexAttrib();
-
     /**
      * Applies the darkening area.
      */
     void Draw();
 
 private:
     PresetState& m_presetState; //!< The global preset state.
-    float m_aspectY{}; //!< Previous Y aspect ration.
+    Renderer::Mesh m_mesh; //!< The "diamond" mesh.
+    float m_aspectY{}; //!< Previous Y aspect ratio.
 };
 
 } // namespace MilkdropPreset