Added SDL+OpenGL 2D rendering backend (ony basic features)

rend2d/servers/sdl_gl_driver.cpp

@@ -0,0 +1,321 @@
+#include "sdl_gl_driver.hpp"
+
+#include <SDL.h>
+#include <SDL_image.h>
+#include <SDL_opengl.h>
+#include <stdexcept>
+#include <assert.h>
+
+using namespace Mangle::Rend2D;
+
+void SDLGL_Sprite::draw(Sprite *s,              // Must be SDLGL_Sprite
+                      int x, int y,             // Destination position
+                      int sx, int sy,           // Source position
+                      int w, int h              // Amount to draw. -1 means remainder.
+                      )
+{
+  // Get source surface
+  SDLGL_Sprite *other = dynamic_cast<SDLGL_Sprite*>(s);
+  assert(other != NULL);
+  SDL_Surface *img = other->getSurface();
+
+  // Check coordinate validity
+  assert(sx <= img->w     && sy <= img->h);
+  assert(x  <= surface->w && y  <= surface->h);
+  assert(sx >= 0 && sy >= 0);
+
+  // Compute width and height if necessary
+  if(w == -1) w = img->w - sx;
+  if(h == -1) h = img->h - sy;
+
+  // Check them if they're valid
+  assert(w >= 0 && w <= img->w);
+  assert(h >= 0 && h <= img->h);
+
+  SDL_Rect dest;
+  dest.x = x;
+  dest.y = y;
+  dest.w = w;
+  dest.h = h;
+
+  SDL_Rect src;
+  src.x = sx;
+  src.y = sy;
+  src.w = w;
+  src.h = h;
+
+  // Do the Blitman
+  SDL_BlitSurface(img, &src, surface, &dest);
+}
+
+SDLGL_Sprite::SDLGL_Sprite(SDL_Surface *s, bool autoDelete)
+  : surface(s), autoDel(autoDelete)
+{
+  assert(surface != NULL);
+}
+
+SDLGL_Sprite::~SDLGL_Sprite()
+{
+  if(autoDel)
+    SDL_FreeSurface(surface);
+}
+
+void SDLGL_Sprite::fill(int value)
+{
+  SDL_FillRect(surface, NULL, value);
+}
+
+int SDLGL_Sprite::width()  { return surface->w; }
+int SDLGL_Sprite::height() { return surface->h; }
+
+SDLGLDriver::SDLGLDriver() : display(NULL), realDisp(NULL)
+{
+  if (SDL_InitSubSystem( SDL_INIT_VIDEO ) == -1)
+    throw std::runtime_error("Error initializing SDL video");
+}
+SDLGLDriver::~SDLGLDriver()
+{
+  if(display) delete display;
+  SDL_Quit();
+}
+
+// Surface used for the screen. Since OpenGL surfaces must have sizes
+// that are powers of 2, we have to "fake" the returned display size
+// to match the screen, not the surface itself. If we don't use this,
+// the client program will get confused about the actual size of our
+// screen, thinking it is bigger than it is.
+struct FakeSizeSprite : SDLGL_Sprite
+{
+  int fakeW, fakeH;
+
+  FakeSizeSprite(SDL_Surface *s, int fw, int fh)
+    : SDLGL_Sprite(s), fakeW(fw), fakeH(fh)
+  {}
+
+  int width() { return fakeW; }
+  int height() { return fakeH; }
+};
+
+static int makePow2(int num)
+{
+  assert(num);
+  if((num & (num-1)) != 0)
+    {
+      int cnt = 0;
+      while(num)
+        {
+          num >>= 1;
+          cnt++;
+        }
+      num = 1 << cnt;
+    }
+  return num;
+}
+
+void SDLGLDriver::setVideoMode(int width, int height, int bpp, bool fullscreen)
+{
+  unsigned int flags;
+
+  if(display) delete display;
+
+  flags = SDL_OPENGL;
+
+  if (fullscreen)
+    flags |= SDL_FULLSCREEN;
+
+  SDL_GL_SetAttribute( SDL_GL_DOUBLEBUFFER, 1 );
+  SDL_GL_SetAttribute( SDL_GL_SWAP_CONTROL, 1 );
+
+  // Create the surface and check it
+  screen = SDL_SetVideoMode(width, height, bpp, flags);
+  if(screen == NULL)
+    throw std::runtime_error("Failed setting SDL video mode");
+
+  // Expand width and height to be powers of 2
+  int width2 = makePow2(width);
+  int height2 = makePow2(height);
+
+  // Create a new SDL surface of this size
+  const SDL_PixelFormat& fmt = *(screen->format);
+  realDisp = SDL_CreateRGBSurface(SDL_SWSURFACE,width2,height2,
+                                  fmt.BitsPerPixel,
+                                  fmt.Rmask,fmt.Gmask,fmt.Bmask,fmt.Amask);
+
+  // Create a sprite directly representing the display surface. This
+  // allows the user to blit to it directly.
+  display = new FakeSizeSprite(realDisp, width, height);
+
+  // Set up the OpenGL format
+  nOfColors = fmt.BytesPerPixel;
+
+  if(nOfColors == 4)
+    {
+      if (fmt.Rmask == 0x000000ff)
+        texture_format = GL_RGBA;
+      else
+        texture_format = GL_BGRA;
+    }
+  else if(nOfColors == 3)
+    {
+      if (fmt.Rmask == 0x000000ff)
+        texture_format = GL_RGB;
+      else
+        texture_format = GL_BGR;
+    }
+  else
+    assert(0 && "unsupported screen format");
+
+  glEnable(GL_TEXTURE_2D);
+
+  // Have OpenGL generate a texture object handle for us
+  glGenTextures( 1, &texture );
+ 
+  // Bind the texture object
+  glBindTexture( GL_TEXTURE_2D, texture );
+ 
+  // Set the texture's stretching properties
+  glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
+  glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
+}
+
+void SDLGLDriver::updateNoSwap()
+{
+  if(!realDisp) return;
+
+  // Fist, set up the screen texture:
+
+  // Bind the texture object
+  glBindTexture( GL_TEXTURE_2D, texture );
+
+  // Edit the texture object's image data
+  glTexImage2D( GL_TEXTURE_2D, 0, nOfColors, realDisp->w, realDisp->h, 0,
+                texture_format, GL_UNSIGNED_BYTE, realDisp->pixels );
+
+  glClear(GL_COLOR_BUFFER_BIT| GL_DEPTH_BUFFER_BIT);
+  glLoadIdentity();
+
+  // OpenGL barf. Set up the projection to match our screen
+  int vPort[4];
+  glGetIntegerv(GL_VIEWPORT, vPort);
+  glMatrixMode(GL_PROJECTION);
+  glPushMatrix();
+  glLoadIdentity();
+  glOrtho(0, vPort[2], 0, vPort[3], -1, 1);
+  glMatrixMode(GL_MODELVIEW);
+  glPushMatrix();
+  glLoadIdentity();
+
+  glBegin( GL_QUADS );
+
+  // Bottom-left vertex (corner)
+  glTexCoord2i( 0, 0 );
+  glVertex3f(0,0,0);
+	
+  // Bottom-right vertex (corner)
+  glTexCoord2i( 1, 0 );
+  glVertex3f( realDisp->w, 0, 0.f );
+	
+  // Top-right vertex (corner)
+  glTexCoord2i( 1, 1 );
+  glVertex3f( realDisp->w, realDisp->h, 0.f );
+	
+  // Top-left vertex (corner)
+  glTexCoord2i( 0, 1 );
+  glVertex3f( 0, realDisp->h, 0.f );
+  glEnd();
+
+  /*
+  glBegin(GL_TRIANGLES);
+    glColor3ub(255, 0, 0);
+    glVertex2d(0, 0);
+
+    glColor3ub(0, 255, 0);
+    glVertex2d(100,0);
+
+    glColor3ub(0, 0, 255);
+    glVertex2d(50, 50);
+  glEnd();
+  */
+
+  glMatrixMode(GL_PROJECTION);
+  glPopMatrix();   
+  glMatrixMode(GL_MODELVIEW);
+  glPopMatrix();	
+}
+
+void SDLGLDriver::swap()
+{
+  SDL_GL_SwapBuffers();
+}
+
+void SDLGLDriver::update()
+{
+  updateNoSwap();
+  swap();
+}
+
+/// Set the window title, as well as the title of the window when
+/// "iconified"
+void SDLGLDriver::setWindowTitle(const std::string &title,
+                               const std::string &icon)
+{
+  SDL_WM_SetCaption( title.c_str(), icon.c_str() );
+}
+
+// Convert the given surface to display format.
+static SDL_Surface* convertImage(SDL_Surface* surf)
+{
+  if(surf != NULL)
+    {
+      // Convert the image to the display buffer format, for faster
+      // blitting
+      SDL_Surface *surf2 = SDL_DisplayFormat(surf);
+      SDL_FreeSurface(surf);
+      surf = surf2;
+    }
+  return surf;
+}
+
+/// Load sprite from an image file, using SDL_image.
+Sprite* SDLGLDriver::loadImage(const std::string &file)
+{
+  SDL_Surface *surf = IMG_Load(file.c_str());
+  surf = convertImage(surf);
+  if(surf == NULL)
+    throw std::runtime_error("SDL failed to load image file '" + file + "'");
+  return spriteFromSDL(surf);
+}
+
+/// Load sprite from an SDL_RWops structure. autoFree determines
+/// whether the RWops struct should be closed/freed after use.
+Sprite* SDLGLDriver::loadImage(SDL_RWops *src, bool autoFree)
+{
+  SDL_Surface *surf = IMG_Load_RW(src, autoFree);
+  surf = convertImage(surf);
+  if(surf == NULL)
+    throw std::runtime_error("SDL failed to load image");
+  return spriteFromSDL(surf);
+}
+
+/// Load a sprite from an image file stored in memory. Uses
+/// SDL_image.
+Sprite* SDLGLDriver::loadImage(const void* data, size_t size)
+{
+  SDL_RWops *rw = SDL_RWFromConstMem(data, size);
+  return loadImage(rw, true);
+}
+
+void SDLGLDriver::setGamma(float red, float green, float blue)
+{
+  SDL_SetGamma(red,green,blue);
+}
+
+/// Convert an existing SDL surface into a sprite
+Sprite* SDLGLDriver::spriteFromSDL(SDL_Surface *surf, bool autoFree)
+{
+  assert(surf);
+  return new SDLGL_Sprite(surf, autoFree);
+}
+
+void SDLGLDriver::sleep(int ms) { SDL_Delay(ms); }
+unsigned int SDLGLDriver::ticks() { return SDL_GetTicks(); }

rend2d/servers/sdl_gl_driver.hpp

@@ -0,0 +1,132 @@
+#ifndef MANGLE_DRAW2D_SDLGL_H
+#define MANGLE_DRAW2D_SDLGL_H
+
+/** This driver is similar to SDLDriver, except that it uses SDL on
+    top of OpenGL.
+
+    I've decided to make it a separate file instead of just adding
+    optional OpenGL support to the original, so that pure SDL users
+    don't have to add OpenGL as a dependency.
+ */
+
+#include "../driver.hpp"
+
+// Predeclarations keep the streets safe at night
+struct SDL_Surface;
+struct SDL_RWops;
+
+namespace Mangle
+{
+  namespace Rend2D
+  {
+    /// SDL-implementation of Sprite
+    struct SDLGL_Sprite : Sprite
+    {
+      /** Draw a sprite in the given position. Can only draw other SDL
+          sprites.
+      */
+      void draw(Sprite *s,                // Must be SDLGL_Sprite
+                int x, int y,             // Destination position
+                int sx=0, int sy=0,       // Source position
+                int w=-1, int h=-1        // Amount to draw. -1 means remainder.
+                );
+
+      SDLGL_Sprite(SDL_Surface *s, bool autoDelete=true);
+      ~SDLGL_Sprite();
+
+      // Information retrieval
+      virtual int width();
+      virtual int height();
+      SDL_Surface *getSurface() { return surface; }
+
+      // Fill with a given pixel value
+      void fill(int value);
+
+    private:
+      // The SDL surface
+      SDL_Surface* surface;
+
+      // If true, delete this surface when the canvas is destructed
+      bool autoDel;
+    };
+
+    class SDLGLDriver : public Driver
+    {
+      // The main display surface
+      SDLGL_Sprite *display;
+
+      // The screen surface. This is completely unused.
+      SDL_Surface *screen;
+
+      // The display surface and main GL texture. These are used when
+      // drawing the entire screen as one surface, as a drop-in
+      // replacement for SDLDriver.
+      SDL_Surface *realDisp;
+      unsigned int texture;
+      int nOfColors, texture_format;
+
+    public:
+      SDLGLDriver();
+      ~SDLGLDriver();
+
+      /// Sets the video mode. Will create the window if it is not
+      /// already set up. Note that for SDL, bpp=0 means use current
+      /// bpp.
+      void setVideoMode(int width, int height, int bpp=0, bool fullscreen=false);
+
+      /// Update the screen
+      void update();
+
+      /// Calls SDL_GL_SwapBuffers
+      void swap();
+
+      /// Draw surface to screen but do not call SDL_GL_SwapBuffers()
+      void updateNoSwap();
+
+      /// Set the window title, as well as the title of the window
+      /// when "iconified"
+      void setWindowTitle(const std::string &title,
+                          const std::string &icon);
+
+      // Include overloads from our Glorious parent
+      using Driver::setWindowTitle;
+
+      /// Load sprite from an image file, using SDL_image.
+      Sprite* loadImage(const std::string &file);
+
+      /// Load sprite from an SDL_RWops structure. autoFree determines
+      /// whether the RWops struct should be closed/freed after use.
+      Sprite* loadImage(SDL_RWops *src, bool autoFree=false);
+
+      /// Load a sprite from an image file stored in memory. Uses
+      /// SDL_image.
+      Sprite* loadImage(const void* data, size_t size);
+
+      /// Set gamma value
+      void setGamma(float gamma) { setGamma(gamma,gamma,gamma); }
+
+      /// Set gamma individually for red, green, blue
+      void setGamma(float red, float green, float blue);
+
+      /// Convert an existing SDL surface into a sprite
+      Sprite* spriteFromSDL(SDL_Surface *surf, bool autoFree = true);
+
+      // Get width and height
+      int width()  { return display ? display->width()  : 0; }
+      int height() { return display ? display->height() : 0; }
+
+      /// Get the screen sprite
+      Sprite *getScreen() { return display; }
+
+      /// Not really a graphic-related function, but very
+      /// handly. Sleeps the given number of milliseconds using
+      /// SDL_Delay().
+      void sleep(int ms);
+
+      /// Get the number of ticks since SDL initialization, using
+      /// SDL_GetTicks().
+      unsigned int ticks();
+    };
+  }
+}
+#endif

rend2d/tests/Makefile

@@ -1,9 +1,15 @@
-GCC=g++ -Wall
+GCC=g++ -Wall -Werror
 
-all: sdl_test
+all: sdl_test sdl_move_test sdlgl_move_test
 
 sdl_test: sdl_test.cpp
 	$(GCC) $< ../servers/sdl_driver.cpp -o $@ -I/usr/include/SDL/ -lSDL -lSDL_image
 
+sdl_move_test: sdl_move_test.cpp ../servers/sdl_driver.cpp
+	$(GCC) $^ -o $@ -I/usr/include/SDL/ -lSDL -lSDL_image
+
+sdlgl_move_test: sdlgl_move_test.cpp ../servers/sdl_gl_driver.cpp
+	$(GCC) $^ -o $@ -I/usr/include/SDL/ -lSDL -lSDL_image -lGL
+
 clean:
 	rm *_test

rend2d/tests/sdl_move_test.cpp

@@ -0,0 +1,30 @@
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+#include "../servers/sdl_driver.hpp"
+
+using namespace Mangle::Rend2D;
+
+int main()
+{
+  SDLDriver sdl;
+
+  sdl.setVideoMode(640,480,0,false);
+  sdl.setWindowTitle("Testing 123");
+  Sprite *screen = sdl.getScreen();
+  const char* imgName = "tile1-blue.png";
+  Sprite *image = sdl.loadImage(imgName);
+
+  for(int frames=0; frames<170; frames++)
+    {
+      screen->fill(0);
+      for(int j=0; j<10; j++)
+        for(int i=0; i<25; i++)
+          screen->draw(image, 2*frames+30*j, 20*i);
+      sdl.update();
+      sdl.sleep(10);
+    }
+  return 0;
+}

rend2d/tests/sdlgl_move_test.cpp

@@ -0,0 +1,31 @@
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+#include "../servers/sdl_gl_driver.hpp"
+
+using namespace Mangle::Rend2D;
+
+int main()
+{
+  SDLGLDriver sdl;
+
+  sdl.setVideoMode(640,480,0,false);
+  sdl.setWindowTitle("Testing 123");
+  Sprite *screen = sdl.getScreen();
+  const char* imgName = "tile1-blue.png";
+  Sprite *image = sdl.loadImage(imgName);
+
+  for(int frames=0; frames<170; frames++)
+    {
+      screen->fill(0);
+      for(int j=0; j<10; j++)
+        for(int i=0; i<25; i++)
+          screen->draw(image, 2*frames+30*j, 20*i);
+      sdl.update();
+      sdl.sleep(5);
+    }
+
+  return 0;
+}