SDLGL code move

include/ZE_Includes.h

@@ -14,7 +14,7 @@
 
     ZE_*.h files should only include this file and any other ZE_*.h files that they need, External Library or C/C++ Standard Library
     files should be included from within this file.
-    $Id: ZE_Includes.h,v 1.19 2003/10/13 20:59:30 cozman Exp $<br>
+    $Id: ZE_Includes.h,v 1.20 2003/10/13 21:40:05 cozman Exp $<br>
     \author James Turk
 **/
 
@@ -26,7 +26,6 @@
 #include "SDL.h"
 #if (GFX_BACKEND == ZE_OGL)
 #include "SDL_opengl.h"
-#include "external/SDLGL_Util.h"
 #endif
 #ifdef USE_SDL_IMAGE
 #include "SDL_image.h"

include/ZE_Utility.h

@@ -14,7 +14,7 @@
 
     Definition file for ZEngine Utilities which are used throughout the engine and can be used in
     conjunction with ZEngine.
-    <br>$Id: ZE_Utility.h,v 1.7 2003/10/05 19:42:34 cozman Exp $<br>
+    <br>$Id: ZE_Utility.h,v 1.8 2003/10/13 21:40:05 cozman Exp $<br>
     \author James Turk
 **/
 
@@ -42,8 +42,8 @@ std::string FormatStr(const char *fmtstr, ...);
     \brief Extracts a SDL_RWops memory structure from a zip archive.
 
     Attempts to open a file from within a zipfile and return a SDL_RWops which can be used
-    to load a resource from memory.  Used by 'LoadFromZip' members of ZImage/ZSound/ZFont
+    to load a resource from memory.
-    so generally not called.
+    Used internally, generally shouldn't be called by users.
     \param zipname Name of zip-format archive to open.
     \param filename Name of file within archive to access.
     \return On success, pointer to SDL_RWops, on failure, NULL.  
@@ -51,6 +51,31 @@ std::string FormatStr(const char *fmtstr, ...);
 **/
 SDL_RWops* RWFromZip(std::string zipname, std::string filename);
 
+/*!
+    \brief Rounds a number up to the nearest power of two.
+
+    Rounds a number up to the next highest power of two, used for OpenGL textures. (From testgl.c)
+    Used internally, generally shouldn't be called by users.
+    \param in Number to round up.
+    \return num rounded up to closest power of two.
+    \since 0.8.6
+**/
+int PowerOfTwo(int num);
+
+/*!
+    \brief Converts an SDL_Surface to an OpenGL texture ID.
+
+    Given an SDL_Surface returns a texture ID representing the OpenGL
+    texture assigned to that surface.  Also returns texture coordinates
+    via texcoord parameter. (From SDL_GL_LoadTexture in testgl.c)
+    Used internally, generally shouldn't be called by users.
+    \param surface SDL_Surface to assign an OpenGL ID, returns unmodified.
+    \param texcoord Should be an array of 4 GLfloat, assigned texture coordinates for OpenGL use.
+    \return OpenGL texture ID for SDL_Surface, 0 if an error occurs.
+    \since 0.8.6
+**/
+GLuint SurfaceToTexture(SDL_Surface *surface, GLfloat *texcoord);
+
 /*!
     \brief Properly free SDL_Surface. 
     

src/ZE_Utility.cpp

@@ -13,7 +13,7 @@
     \brief Source file for ZEngine utility functions.
 
     Source file containing open utilities for use inside and alongside ZEngine.
-    <br>$Id: ZE_Utility.cpp,v 1.11 2003/09/24 02:03:18 cozman Exp $<br>
+    <br>$Id: ZE_Utility.cpp,v 1.12 2003/10/13 21:40:05 cozman Exp $<br>
     \author James Turk
 **/
 
@@ -75,6 +75,82 @@ SDL_RWops* RWFromZip(std::string zipname, std::string filename)
     return SDL_RWFromMem(buffer, info.uncompressed_size);   //return buffer in RW form
 }
 
+//from SDL's testgl.c power_of_two
+int PowerOfTwo(int num)
+{
+    int value = 1;
+
+    while(value < num) //texture coord must be >= input
+        value <<= 1;     //value <<= 1 is the same as value *= 2
+    return value;
+}
+
+//from SDL's testgl.c SDL_GL_LoadTexture
+GLuint SurfaceToTexture(SDL_Surface *surface, GLfloat *texcoord)
+{
+    GLuint texture;
+    int w, h;
+    SDL_Surface *temp;
+    SDL_Rect area;
+    Uint32 saved_flags;
+    Uint8  saved_alpha;
+
+    //expand width and height to nearest powers of 2
+    w = PowerOfTwo(surface->w);
+    h = PowerOfTwo(surface->h);
+    texcoord[0] = 0.0f; //min X
+    texcoord[1] = 0.0f; //min Y
+    texcoord[2] = (GLfloat)surface->w / w;  //max X
+    texcoord[3] = (GLfloat)surface->h / h;  //max Y
+
+    temp = SDL_CreateRGBSurface(
+        SDL_SWSURFACE,
+        w, h,
+        32,
+#if SDL_BYTEORDER == SDL_LIL_ENDIAN //endian specific color masks
+        0x000000FF, 
+        0x0000FF00, 
+        0x00FF0000, 
+        0xFF000000
+#else
+        0xFF000000,
+        0x00FF0000, 
+        0x0000FF00, 
+        0x000000FF
+#endif
+    );
+    if(!temp)  //failure in CreateRGBSurface
+        return 0;
+
+    //save alpha
+    saved_flags = surface->flags&(SDL_SRCALPHA|SDL_RLEACCELOK);
+    saved_alpha = surface->format->alpha;
+    if((saved_flags & SDL_SRCALPHA) == SDL_SRCALPHA)
+        SDL_SetAlpha(surface, 0, 0);
+
+    //copy surface (do not alter passed surface to allow this function to be used in special situations)
+    area.x = 0;
+    area.y = 0;
+    area.w = static_cast<Sint16>(surface->w);
+    area.h = static_cast<Sint16>(surface->h);
+    SDL_BlitSurface(surface, &area, temp, &area);
+
+    //restore saved alpha
+    if((saved_flags & SDL_SRCALPHA) == SDL_SRCALPHA)
+        SDL_SetAlpha(surface, saved_flags, saved_alpha);
+
+    //create the OpenGL texture
+    glGenTextures(1, &texture); 
+    //setup texture parmaters
+    glBindTexture(GL_TEXTURE_2D, texture);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16, w, h, 0, GL_RGBA, GL_UNSIGNED_BYTE, temp->pixels);
+    SDL_FreeSurface(temp); //temp surface no longer needed
+
+    return texture;
+}
+
 //Each of the Free*s safely frees & NULLs the pointer
 void FreeImage(SDL_Surface *&image)
 {

src/ZE_ZImage.cpp

@@ -13,7 +13,7 @@
     \brief Source file for ZImage.
 
     Implementation of ZImage, the Image class for ZEngine.
-    <br>$Id: ZE_ZImage.cpp,v 1.48 2003/10/11 16:21:50 cozman Exp $<br>
+    <br>$Id: ZE_ZImage.cpp,v 1.49 2003/10/13 21:40:05 cozman Exp $<br>
     \author James Turk
 **/
 
@@ -172,7 +172,7 @@ void ZImage::Attach(SDL_Surface *surface)
     
         rWidth = static_cast<float>(surface->w);
         rHeight = static_cast<float>(surface->h);
-        rTexID = SDL_GL_LoadTexture(surface,coord); //major helper, not written by me, from libsdl.org
+        rTexID = SurfaceToTexture(surface,coord);
         rTexMinX = coord[0];
         rTexMinY = coord[1];
         rTexMaxX = coord[2];