OpenGL Rotation and Zooming.

include/ZE_ZImage.h

@@ -13,7 +13,7 @@
 File: ZE_ZImage.h <br>
 Description: Header file for core ZEngine Image and Texture Object. <br>
 Author(s): James Turk, Gamer Tazar <br>
-$Id: ZE_ZImage.h,v 1.2 2002/12/01 07:56:17 cozman Exp $<br>
+$Id: ZE_ZImage.h,v 1.3 2002/12/02 00:36:35 cozman Exp $<br>
 
     \file ZE_ZImage.h
     \brief Definition file for ZImage.
@@ -149,6 +149,24 @@ class ZImage : public ZObject
         **/
         void SetColorKey(Uint8 red, Uint8 green, Uint8 blue);
 
+        /*!
+            \brief Stretch the image by a certain X and Y factor.
+
+            Stretch image using a factor to multiply width and height by.
+            \param xFactor Stretch factor for width. [newWidth = oldWidth * xStretch]
+            \param yFactor Stretch factor for height. [newHeight = oldHeight * yStretch]
+        **/
+        void Stretch(float xFactor, float yFactor);
+
+        /*!
+            \brief Resizes an image, stretching to new size.
+
+            Stretch image to new width and height.
+            \param width New width to stretch image to.
+            \param height New height to stretch image to.
+        **/
+        void Resize(unsigned int width, unsigned int height);
+
         /*!
             \brief OpenGL related bind call.
 
@@ -164,7 +182,17 @@ class ZImage : public ZObject
             \param x X coord to draw Image to.
             \param y Y coord to draw Image to.
         **/
-        void Draw(int x, int y);
+        void Draw(float x, float y);
+
+        /*!
+            \brief Draw Image rotated to screen.
+
+            Image is rotated about it's own center by specified angle, then drawn to screen.
+            \param x X coord to draw Image to.
+            \param y Y coord to draw Image to.
+            \param angle Angle in degrees to rotate image.
+        **/
+        void DrawRotated(int x, int y, float angle);
 
         /////////////
         //Accessors//

include/ZEngine.h

@@ -3,7 +3,7 @@
 File: ZEngine.h <br>
 Description: Public Header File for ZEngine. <br>
 Author(s): James Turk <br>
-$Id: ZEngine.h,v 1.3 2002/12/01 07:56:17 cozman Exp $<br>
+$Id: ZEngine.h,v 1.4 2002/12/02 00:36:35 cozman Exp $<br>
 
     \file ZEngine.h
     \brief Header file for ZEngine.
@@ -16,16 +16,17 @@ $Id: ZEngine.h,v 1.3 2002/12/01 07:56:17 cozman Exp $<br>
     \mainpage ZEngine Documentation
 
     \author James Turk
-    \version 0.7.7
+    \version 0.7.8
     \date 1 December, 2002
 
     \section ZEngine About ZEngine
     <br>
-    ZEngine is designed to wrap common interfaces of the SDL API in an Object Oriented manner.  It is licensed under 
+    ZEngine is designed to wrap common interfaces of the SDL API in an Object Oriented manner. <br> It is licensed under 
-    a very liberal BSD-style license, and anyone is free to suggest or implement changes to be added to the Engine.  In addition
+    a very liberal BSD-style license, and anyone is free to suggest or implement changes to be added to the Engine.<br>
-    ZEngine hopes to provide a core engine which can be used to develop a game without having to rewrite large amounts
+    In addition ZEngine aims to provide a core engine which can be used to develop a game without having to 
-    of code. As of version 0.7.7 ZEngine uses OpenGL rather than SDL to do 2D drawing, thus increasing the use of the engine
+    rewrite large amounts of code.<br>
-    and making the engine much faster in most test cases.
+    As of version 0.7.7 ZEngine uses OpenGL rather than SDL to do 2D drawing, thus increasing the uses of the engine
+    and making the engine much faster in most test cases.<br>
     
     \section Licensing Licensing
     <br><pre>

src/ZE_ZImage.cpp

@@ -13,7 +13,7 @@
 File: ZE_ZImage.cpp <br>
 Description: Implementation source file for core ZEngine Image or Texture Object. <br>
 Author(s): James Turk, Gamer Tazar <br>
-$Id: ZE_ZImage.cpp,v 1.3 2002/12/01 07:56:17 cozman Exp $<br>
+$Id: ZE_ZImage.cpp,v 1.4 2002/12/02 00:36:35 cozman Exp $<br>
 
     \file ZE_ZImage.cpp
     \brief Source file for ZImage.
@@ -151,23 +151,55 @@ void ZImage::SetColorKey(Uint8 red, Uint8 green, Uint8 blue)
         LogError("ZImage not initialized in ZImage::SetColorKey.");
 }
 
+void ZImage::Stretch(float xFactor, float yFactor)
+{
+    rWidth = static_cast<unsigned int>(xFactor*rWidth);
+    rHeight = static_cast<unsigned int>(yFactor*rHeight);
+}
+
+void ZImage::Resize(unsigned int width, unsigned int height)
+{
+    rWidth = width;
+    rHeight = height;
+}
+
 void ZImage::Bind()
 {
     glBindTexture(GL_TEXTURE_2D, rTexID);
 }
 
-void ZImage::Draw(int x, int y)
+void ZImage::Draw(float x, float y)
 {
     Bind(); 
 
     glBegin(GL_TRIANGLE_STRIP);
-        glTexCoord2f(0.0f,0.0f);            glVertex2i(x, y);
+        glTexCoord2f(0.0f,0.0f);            glVertex2f(x, y);
-        glTexCoord2f(rTexMaxX,0.0f);        glVertex2i(x+rWidth, y);
+        glTexCoord2f(rTexMaxX,0.0f);        glVertex2f(x+rWidth, y);
-        glTexCoord2f(0.0f,rTexMaxY);        glVertex2i(x, y+rHeight);
+        glTexCoord2f(0.0f,rTexMaxY);        glVertex2f(x, y+rHeight);
-        glTexCoord2f(rTexMaxX,rTexMaxY);    glVertex2i(x+rWidth, y+rHeight);
+        glTexCoord2f(rTexMaxX,rTexMaxY);    glVertex2f(x+rWidth, y+rHeight);
     glEnd();
 }
 
+void ZImage::DrawRotated(int x, int y, float angle)
+{
+    float cX,cY; //center variables
+
+    cX = rWidth/2.0f;
+    cY = rHeight/2.0f;
+
+    glPushMatrix();
+    glTranslatef(x+cX,y+cY,0);
+    glRotatef(angle,0,0,1.0f);
+    Bind(); 
+    glBegin(GL_TRIANGLE_STRIP);
+        glTexCoord2f(0.0f,0.0f);            glVertex2f(-cX, -cY);
+        glTexCoord2f(rTexMaxX,0.0f);        glVertex2f(-cX+rWidth, -cY);
+        glTexCoord2f(0.0f,rTexMaxY);        glVertex2f(-cX, -cY+rHeight);
+        glTexCoord2f(rTexMaxX,rTexMaxY);    glVertex2f(-cX+rWidth, -cY+rHeight);
+    glEnd();
+    glPopMatrix();
+}
+
 bool ZImage::IsLoaded()
 {
     return glIsTexture(rTexID) == GL_TRUE;

test/ZImageTest.cpp

@@ -34,17 +34,17 @@ void Initialize()
 void Test()
 {
     ZEngine *engine = ZEngine::GetInstance();
+    float angle=0.0f;
 
     //Open and Setup all the Images//
     SDL_Surface *temp;
-    ZImage image1, image2("data/test01.bmp"), image3(image2.Surface(),20,20,20,20), textImage;
+    ZImage image1, image2("data/test01.bmp"), image3(image2.Surface(),5,5,20,20), textImage;
     ZFont font("data/almontew.ttf",30);
 
     temp = SDL_LoadBMP("data/test02.bmp");    //this is a separate surface
     image1.Attach(temp);    //this attaches the surface into itself
     temp = NULL;    //and temp will now be controlled and freed by image1
     image1.SetColorKey(255,0,255);
-//    image2.SetAlpha(75);
     image2.SetColorKey(255,0,255);
     font.SetColor(0,255,0);
     font.SetBGColor(0,0,255);
@@ -66,7 +66,11 @@ void Test()
         engine->Clear();    //clear screen
         //draw the images//
         image1.Draw(0,0);
-        image2.Draw(100,0);
+        
+        image2.DrawRotated(100,0,angle);
+        if(++angle > 360)
+            angle = 0.0f;
+
         image3.Draw(200,0);
         textImage.Draw(0,100);
         engine->UpdateScreen();    //update the screen