Implement Pointless Broken Things

[ipdf/code.git] / src / screen.cpp

diff --git a/src/screen.cpp b/src/screen.cpp
index e97995c..624e55d 100644 (file)
--- a/src/screen.cpp
+++ b/src/screen.cpp
@@ -142,3 +142,55 @@ void Screen::ScreenShot(const char * filename) const
        delete [] pixels;
        Debug("Succeeded!");
 }
+
+/**
+ * Render a BMP
+ * NOT PART OF THE DOCUMENT FORMAT
+ */
+void Screen::RenderBMP(const char * filename) const
+{
+       SDL_Surface * bmp = SDL_LoadBMP(filename);
+       if (bmp == NULL)
+               Fatal("Failed to load BMP from %s - %s", filename, SDL_GetError());
+
+       int w = bmp->w;
+       int h = bmp->h;
+
+       GLenum texture_format; 
+       switch (bmp->format->BytesPerPixel)
+       {
+               case 4: //contains alpha
+                       texture_format = (bmp->format->Rmask == 0x000000FF) ? GL_RGBA : GL_BGRA;
+                       break;
+               case 3: //does not contain alpha
+                       texture_format = (bmp->format->Rmask == 0x000000FF) ? GL_RGB : GL_BGR;  
+                       break;
+               default:
+                       Fatal("Could not understand SDL_Surface format (%d colours)", bmp->format->BytesPerPixel);
+                       break;  
+       }
+       Debug("SDL_Surface %d BytesPerPixel, format %d (RGB = %d, BGR = %d, RGBA = %d, BGRA = %d)", bmp->format->BytesPerPixel, texture_format, GL_RGB, GL_BGR, GL_RGBA, GL_BGRA);
+
+
+       GLuint texID;
+
+       glGenTextures(1, &texID);
+       glBindTexture(GL_TEXTURE_2D, texID);
+       glTexImage2D(GL_TEXTURE_2D, 0, bmp->format->BytesPerPixel, w, h, 0, texture_format, GL_UNSIGNED_BYTE, bmp->pixels);
+       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+
+       glEnable(GL_TEXTURE_2D);
+       glBindTexture(GL_TEXTURE_2D, texID);
+
+       glBegin(GL_QUADS);
+               glTexCoord2i(0,0); glVertex2f(-0.5f*w, -0.5f*h);
+               glTexCoord2i(1,0); glVertex2f(0.5f*w, -0.5f*h);
+               glTexCoord2i(1,1); glVertex2f(0.5f*w, 0.5f*h);
+               glTexCoord2i(0,1); glVertex2f(-0.5*w,0.5*h);
+       glEnd();
+
+       glDisable(GL_TEXTURE_2D);
+
+       //SDL_FreeSurface(bmp); 
+}