[Add] Finally added opengl error checking in DEBUG builds.

src/font.c

@@ -72,6 +72,8 @@ void gl_print(const glFont* ft_font, const double x, const double y,
 
   glPopMatrix(); // Translation matrix.
   glDisable(GL_TEXTURE_2D);
+
+  gl_checkErr();
 }
 
 // Acts just like gl_print, but prints to a max length of max.
@@ -120,6 +122,8 @@ int gl_printMax(const glFont* ft_font, const int max,
   glPopMatrix(); // Translation matrix.
   glDisable(GL_TEXTURE_2D);
 
+  gl_checkErr();
+
   return ret;
 }
 
@@ -173,6 +177,8 @@ int gl_printMid(const glFont* ft_font, const int width, double x, const double y
   glPopMatrix(); // Translation matrix.
   glDisable(GL_TEXTURE_2D);
 
+  gl_checkErr();
+
   return ret;
 }
 
@@ -256,6 +262,8 @@ int gl_printText(const glFont* ft_font, const int width, const int height,
   }
   glDisable(GL_TEXTURE_2D);
 
+  gl_checkErr();
+
   return ret;
 }
 
@@ -407,12 +415,16 @@ static void glFontMakeDList(FT_Face face, char ch, GLuint list_base,
   glEndList();
 
   FT_Done_Glyph(glyph);
+
+  gl_checkErr();
 }
 
 void gl_fontInit(glFont* font, const char* fname, const unsigned int h) {
+  uint32_t bufsize;
+  int i;
+
   if(font == NULL) font = &gl_defFont;
 
-  uint32_t bufsize;
   FT_Byte* buf = pack_readfile(DATA, (fname) ? fname : FONT_DEF, &bufsize);
 
   // Allocatagery.
@@ -443,7 +455,6 @@ void gl_fontInit(glFont* font, const char* fname, const unsigned int h) {
   glGenTextures(128, font->textures);
 
   // Create each of the font display lists.
-  unsigned char i;
   for(i = 0; i < 128; i++)
     glFontMakeDList(face, i, font->list_base, font->textures, font->w);
 

src/lephisto.c

@@ -246,6 +246,8 @@ void main_loop(void) {
   }
   if(toolkit) toolkit_render();
 
+  gl_checkErr(); // Check error every loop.
+
   SDL_GL_SwapBuffers();
 }
 

src/opengl.c

@@ -141,6 +141,8 @@ void gl_screenshot(const char* filename) {
 
   for(i = 0; i < screen->h; i++) rows[i] = screenbuf[screen->h - i - 1];
   write_png(filename, rows, screen->w, screen->h, PNG_COLOR_TYPE_RGB, 8);
+
+  gl_checkErr();
 }
 
 // ================
@@ -235,6 +237,8 @@ static GLuint gl_loadSurface(SDL_Surface* surface, int* rw, int* rh) {
   SDL_UnlockSurface(surface);
   SDL_FreeSurface(surface);
 
+  gl_checkErr();
+
   return texture;
 }
 
@@ -387,6 +391,8 @@ void gl_blitSprite(const glTexture* sprite, const double bx, const double by,
   glEnd();
 
   glDisable(GL_TEXTURE_2D);
+
+  gl_checkErr();
 }
 
 // Just straight out blit the thing at position.
@@ -419,6 +425,8 @@ void gl_blitStatic(const glTexture* texture, const double bx, const double by,
   glEnd();
 
   glDisable(GL_TEXTURE_2D);
+
+  gl_checkErr();
 }
 
 // Bind our precious camera to a vector.
@@ -469,6 +477,8 @@ void gl_drawCircle(const double cx, const double cy, const double r) {
     }
   }
   glEnd();
+
+  gl_checkErr();
 }
 
 // Draw a cirlce in a rect.
@@ -532,7 +542,10 @@ void gl_drawCircleInRect(const double cx, const double cy, const double r,
     }
   }
   glEnd();
+  
+  gl_checkErr();
 }
+#undef PIXEL
 
 // ================
 // GLOBAL.
@@ -564,6 +577,46 @@ static GLboolean gl_hasExt(char* name) {
   return GL_FALSE;
 }
 
+// Check and report if there's been an error.
+void gl_checkErr(void) {
+#ifdef DEBUG
+  GLenum err;
+  char* errstr;
+
+  err = glGetError();
+
+  if(err == GL_NO_ERROR) return; // No error.
+
+  switch(err) {
+    case GL_INVALID_ENUM:
+      errstr = "GL invalid enum";
+      break;
+    case GL_INVALID_VALUE:
+      errstr = "GL invalid operation";
+      break;
+      case GL_INVALID_OPERATION:
+      errstr = "GL invalid operation";
+      break;
+    case GL_STACK_OVERFLOW:
+      errstr = "GL stack overflow";
+      break;
+    case GL_STACK_UNDERFLOW:
+      errstr = "GL stack underflow";
+      break;
+    case GL_OUT_OF_MEMORY:
+      errstr = "GL out of memory";
+      break;
+    case GL_TABLE_TOO_LARGE:
+      errstr = "GL table too large";
+      break;
+    default:
+      errstr = "GL unkown error";
+      break;
+  }
+  WARN("OpenGL error: %s", errstr);
+#endif
+}
+
 // Initialize SDL/OpenGL etc.
 int gl_init(void) {
   int doublebuf, depth, i, j, off, toff, supported;
@@ -683,6 +736,8 @@ int gl_init(void) {
 
   glClear(GL_COLOR_BUFFER_BIT);
 
+  gl_checkErr();
+
   return 0;
 }
 

src/opengl.h

@@ -79,4 +79,5 @@ void gl_exit(void);
 int gl_isTrans(const glTexture* t, const int x, const int y);
 void gl_getSpriteFromDir(int* x, int* y, const glTexture* t, const double dir);
 void gl_screenshot(const char* filename);
+void gl_checkErr(void);