Example of Rendering UI done.

src/dawnopengl/display/shader/Shader.hpp

@@ -208,7 +208,7 @@ namespace Dawn {
               assertNoGLError();
               glBufferData(
                 GL_UNIFORM_BUFFER,
-                structure.size,
+                structure.size * structure.count,
                 (void*)((size_t)&this->data + (size_t)structure.offset),
                 GL_STATIC_DRAW
               );

src/dawnopengl/display/shader/ShaderStructure.hpp

@@ -16,7 +16,7 @@ namespace Dawn {
     size_t offset;
     enum ShaderOpenGLStructureType structureType;
     size_t size;
-    // size_t count;
+    size_t count;
     std::vector<struct ShaderParameter> parameters;
     GLint location = -1;
     GLuint buffer = -1;
@@ -46,12 +46,14 @@ namespace Dawn {
         const enum ShaderOpenGLStructureType structureType,
         std::function<
           void(const T&, std::vector<struct ShaderParameter>&)
-        > getParameters
+        > getParameters,
+        size_t count = 1
       ) {
         this->structureName = structureName;
         this->offset = (size_t)offset;
         this->structureType = structureType;
         this->size = sizeof(T);
+        this->count = count;
         this->parameters = std::vector<struct ShaderParameter>();
 
         T dummy;

src/dawnopengl/display/shader/UIShader.cpp

@@ -4,6 +4,7 @@
 // https://opensource.org/licenses/MIT
 
 #include "display/shader/UIShader.hpp"
+#include "util/Macro.hpp"
 
 using namespace Dawn;
 
@@ -28,10 +29,50 @@ void UIShader::getStages(
         "uniform mat4 u_Projection;\n"
         "uniform mat4 u_View;\n"
         "uniform mat4 u_Model;\n"
+        "struct UIShaderQuad {\n"
+          "mat4 transform;\n"
+          "vec4 quad;\n"
+          "vec4 uv;\n"
+          "vec4 color;\n"
+        "};\n"
+        "layout (std140) uniform ub_Quad {\n"
+          "UIShaderQuad quads[" MACRO_STRINGIFY(UI_SHADER_QUAD_COUNT) "];\n"
+        "};\n"
         "out vec2 o_TextCoord;\n"
+        "out vec4 v_Color;\n"
         "void main() {\n"
-          "gl_Position = u_Projection * u_View * u_Model * vec4(aPos, 1.0);\n"
-          "o_TextCoord = vec2(aTexCoord.x, aTexCoord.y);\n"
+          "vec4 pos;\n"
+          "vec2 coord;\n"
+          "int index = int(aPos.z);\n"
+          "int quadIndex = index / 4;\n"
+          "int vertexIndex = index % 4;\n"
+          "struct UIShaderQuad quad = quads[quadIndex];\n"
+          "if(vertexIndex == 0) {\n"
+            "pos.x = quad.quad.x;\n"
+            "pos.y = quad.quad.y;\n"
+            "coord.x = quad.uv.x;\n"
+            "coord.y = quad.uv.y;\n"
+          "} else if(vertexIndex == 1) {\n"
+            "pos.x = quad.quad.z;\n"
+            "pos.y = quad.quad.y;\n"
+            "coord.x = quad.uv.z;\n"
+            "coord.y = quad.uv.y;\n"
+          "} else if(vertexIndex == 2) {\n"
+            "pos.y = quad.quad.w;\n"
+            "pos.x = quad.quad.x;\n"
+            "coord.x = quad.uv.x;\n"
+            "coord.y = quad.uv.w;\n"
+          "} else if(vertexIndex == 3) {\n"
+            "pos.x = quad.quad.z;\n"
+            "pos.y = quad.quad.w;\n"
+            "coord.x = quad.uv.z;\n"
+            "coord.y = quad.uv.w;\n"
+          "}\n"
+          "pos.z = 0;\n"
+          "pos.w = 1;\n"
+          "gl_Position = u_Projection * u_View * u_Model * quad.transform * pos;\n"
+          "o_TextCoord = coord;\n"
+          "v_Color = quad.color;\n"
         "}"
       );
       
@@ -39,14 +80,10 @@ void UIShader::getStages(
         ShaderStageType::FRAGMENT,
         "#version 330 core\n"
         "in vec2 o_TextCoord;\n"
-        "layout (std140) uniform ub_Color {\n"
-          "vec4 first;\n"
-          "vec3 random;\n"
-          "vec4 second;\n"
-        "};\n"
+        "in vec4 v_Color;\n"
         "out vec4 o_Color;\n"
         "void main() {\n"
-          "o_Color = second;\n"
+          "o_Color = v_Color;\n"
         "}\n"
       );
       break;
@@ -78,28 +115,35 @@ void UIShader::getStages(
     ShaderParameterType::MAT4
   ));
   
-  structures.push_back(ShaderStructure<struct TestStruct>(
-    "ub_Color",
-    &rel->test,
+  structures.push_back(ShaderStructure<struct UIShaderQuad>(
+    "ub_Quad",
+    &rel->quads,
     ShaderOpenGLStructureType::STD140,
-    [&](const struct TestStruct &rel, std::vector<struct ShaderParameter> &parameters) {
+    [&](const struct UIShaderQuad &rel, std::vector<struct ShaderParameter> &parameters) {
       parameters.push_back(ShaderParameter(
-        "first",
-        &rel.first,
+        "u_Transform",
+        &rel.transform,
+        ShaderParameterType::MAT4
+      ));
+
+      parameters.push_back(ShaderParameter(
+        "u_Quad",
+        &rel.quad,
+        ShaderParameterType::VEC4
+      ));
+
+      parameters.push_back(ShaderParameter(
+        "u_UV",
+        &rel.uv,
+        ShaderParameterType::VEC4
+      ));
+
+      parameters.push_back(ShaderParameter(
+        "u_Color",
+        &rel.color,
         ShaderParameterType::COLOR
       ));
-      
-      parameters.push_back(ShaderParameter(
-        "random",
-        &rel.random,
-        ShaderParameterType::VEC3
-      ));
-      
-      parameters.push_back(ShaderParameter(
-        "second",
-        &rel.second,
-        ShaderParameterType::COLOR
-      ));
-    }
+    },
+    2
   ));
 }

src/dawnopengl/display/shader/UIShader.hpp

@@ -7,18 +7,20 @@
 #include "display/shader/Shader.hpp"
 
 namespace Dawn {
-  struct TestStruct {
-    struct Color first;
-    glm::vec3 random;
-    float_t padded;
-    struct Color second;
+  #define UI_SHADER_QUAD_COUNT 32
+
+  struct UIShaderQuad {
+    glm::mat4 transform;
+    glm::vec4 quad;
+    glm::vec4 uv;
+    struct Color color;
   };
   
   struct UIShaderData {
     glm::mat4 projection;
     glm::mat4 view;
     glm::mat4 model;
-    struct TestStruct test;
+    struct UIShaderQuad quads[UI_SHADER_QUAD_COUNT];
   };
 
   class UIShader : public Shader<UIShaderData> {