postprocess is on the way

CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.25)
 
-set(BLT_GRAPHICS_VERSION 0.13.8)
+set(BLT_GRAPHICS_VERSION 0.13.9)
 set(BLT_GRAPHICS_TEST_VERSION 0.0.1)
 
 project(BLT_WITH_GRAPHICS VERSION ${BLT_GRAPHICS_VERSION})

include/blt/gfx/gl_includes.h

@@ -8,9 +8,13 @@
 #ifndef BLT_GL_INCLUDES_H
 #define BLT_GL_INCLUDES_H
 
+#include <blt/std/logging.h>
+
 // emscripten provides its own gl bindings.
 #ifndef __EMSCRIPTEN__
+    
     #include <glad/gl.h>
+
 #else
     #include <GLES2/gl2.h>
     #include <GLES3/gl3.h>
@@ -21,4 +25,40 @@
     #define EGL_EGLEXT_PROTOTYPES
 #endif
 
+namespace blt::gfx
+{
+    inline std::string get_error_message(GLenum error)
+    {
+        switch (error)
+        {
+            case GL_INVALID_ENUM:
+                return "Invalid Enum";
+            case GL_INVALID_VALUE:
+                return "Invalid Value";
+            case GL_INVALID_OPERATION:
+                return "Invalid Operation";
+            case GL_STACK_OVERFLOW:
+                return "Stack Overflow";
+            case GL_STACK_UNDERFLOW:
+                return "Stack Underflow";
+            case GL_OUT_OF_MEMORY:
+                return "Out Of Memory";
+            case GL_INVALID_FRAMEBUFFER_OPERATION:
+                return "Invalid Framebuffer Operation";
+            case GL_INVALID_INDEX:
+                return "Invalid Index";
+        }
+        return std::string("Unknown Error: ") += std::to_string(error);
+    }
+    
+    inline void handle_errors()
+    {
+        GLenum err;
+        while ((err = glGetError()) != GL_NO_ERROR)
+        {
+            BLT_ERROR(get_error_message(err));
+        }
+    }
+}
+
 #endif //BLT_GL_INCLUDES_H

include/blt/gfx/renderer/shaders/pp_screen.frag

@@ -4,7 +4,7 @@ const std::string shader_pp_screen_frag = R"("
 #version 300 es
 precision mediump float;
 
-out vec4 FragColor;
+${LAYOUT_STRING} out vec4 FragColor;
 in vec2 uv;
 in vec2 pos;
 

src/blt/gfx/framebuffer.cpp

@@ -222,7 +222,7 @@ namespace blt::gfx
         fbo.create();
         fbo.bind();
         
-        auto* texture = new texture_gl2D(width, height);
+        auto* texture = new texture_gl2D(width, height, GL_RGBA8);
         fbo.attachTexture(texture, attachment_t::COLOR0);
         
         render_buffer_t depth_rbo = render_buffer_t::make_render_buffer(GL_DEPTH24_STENCIL8, width, height);

src/blt/gfx/renderer/postprocess.cpp

@@ -145,20 +145,21 @@ namespace blt::gfx
     
     void pp_in_place_t::post_draw(frame_buffer_t& previous)
     {
-        draw_buffer.blitTexture(previous, 0, 0, 0, 0, GL_NEAREST, from, to);
-//        previous.bind();
-//        GLenum buf[32];
-//        auto buff_val = static_cast<GLenum>(to);
-//        auto size = buff_val - GL_COLOR_ATTACHMENT0;
-//        for (GLenum i = 0; i < size; i++)
-//            buf[i] = GL_NONE;
-//        buf[size] = buff_val;
-//        glDrawBuffers(static_cast<int>(size) + 1, buf);
-//        glClear(GL_COLOR_BUFFER_BIT);
-//        shader_pass->bind();
-//        glActiveTexture(GL_TEXTURE0);
-//        draw_buffer.getTexture(frame_buffer_t::attachment_t::COLOR0).bind();
-//        pp_engine_t::render_quad();
+//        draw_buffer.blitTexture(previous, 0, 0, 0, 0, GL_NEAREST, from, to);
+        handle_errors();
+        previous.bind();
+        GLenum buf[32];
+        auto to_val = static_cast<GLenum>(to);
+        auto size = to_val - GL_COLOR_ATTACHMENT0;
+        for (GLenum i = 0; i < size; i++)
+            buf[i] = GL_NONE;
+        buf[size] = to_val;
+        glDrawBuffers(static_cast<int>(size) + 1, buf);
+        glClear(GL_COLOR_BUFFER_BIT);
+        shader_pass->bind();
+        glActiveTexture(GL_TEXTURE0);
+        draw_buffer.getTexture(frame_buffer_t::attachment_t::COLOR0).bind();
+        pp_engine_t::render_quad();
     }
     
     void pp_in_place_t::draw(frame_buffer_t& previous)

src/blt/gfx/window.cpp

@@ -27,6 +27,22 @@ void error_callback(int error, const char* description)
     std::abort();
 }
 
+void gl_error_callback(GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei, const GLchar* message, const void*)
+{
+    // do not log performance concerns
+    if (type == GL_DEBUG_TYPE_PERFORMANCE || type == GL_DEBUG_TYPE_OTHER)
+        return;
+    if (type == GL_DEBUG_TYPE_ERROR)
+    {
+        BLT_ERROR("[OpenGL Error] message = '%s', type = 0x%x, severity = 0x%x, source = 0x%x, id = %d",
+                 message, type, severity, source, id);
+    } else
+    {
+        BLT_WARN("[OpenGL Error] message = '%s', type = 0x%x, severity = 0x%x, source = 0x%x, id = %d",
+                 message, type, severity, source, id);
+    }
+}
+
 namespace blt::gfx
 {
     struct
@@ -236,6 +252,9 @@ namespace blt::gfx
         gladLoadGL(glfwGetProcAddress);
 #endif
         
+        glEnable(GL_DEBUG_OUTPUT);
+        glDebugMessageCallback(gl_error_callback, nullptr);
+        
         /* -- Set up our local callbacks, ImGUI will then call these -- */
         create_callbacks();