1 files changed, 152 insertions, 0 deletions
diff --git a/tests/gl_stride.c b/tests/gl_stride.c
new file mode 100644
index 00000000..c254ad5a
--- /dev/null
+++ b/tests/gl_stride.c
@@ -0,0 +1,152 @@
+/*******************************************************************
+ *                                                                 *
+ *                        Using SDL With OpenGL                    *
+ *                                                                 *
+ *                    Tutorial by Kyle Foley (sdw)                 *
+ *                                                                 *
+ * http://gpwiki.org/index.php/SDL:Tutorials:Using_SDL_with_OpenGL *
+ *                                                                 *
+ *******************************************************************/
+
+/*
+THIS WORK, INCLUDING THE SOURCE CODE, DOCUMENTATION
+AND RELATED MEDIA AND DATA, IS PLACED INTO THE PUBLIC DOMAIN.
+
+THE ORIGINAL AUTHOR IS KYLE FOLEY.
+
+THIS SOFTWARE IS PROVIDED AS-IS WITHOUT WARRANTY
+OF ANY KIND, NOT EVEN THE IMPLIED WARRANTY OF
+MERCHANTABILITY. THE AUTHOR OF THIS SOFTWARE,
+ASSUMES _NO_ RESPONSIBILITY FOR ANY CONSEQUENCE
+RESULTING FROM THE USE, MODIFICATION, OR
+REDISTRIBUTION OF THIS SOFTWARE.
+*/
+
+#if !EMSCRIPTEN
+#define USE_GLEW 0
+#endif
+
+#if USE_GLEW
+#include "GL/glew.h"
+#endif
+
+#include "SDL/SDL.h"
+#include "SDL/SDL_image.h"
+#if !USE_GLEW
+#include "SDL/SDL_opengl.h"
+#endif
+
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+
+int main(int argc, char *argv[])
+{
+    SDL_Surface *screen;
+
+    // Slightly different SDL initialization
+    if ( SDL_Init(SDL_INIT_VIDEO) != 0 ) {
+        printf("Unable to initialize SDL: %s\n", SDL_GetError());
+        return 1;
+    }
+
+    SDL_GL_SetAttribute( SDL_GL_DOUBLEBUFFER, 1 ); // *new*
+
+    screen = SDL_SetVideoMode( 640, 480, 16, SDL_OPENGL ); // *changed*
+    if ( !screen ) {
+        printf("Unable to set video mode: %s\n", SDL_GetError());
+        return 1;
+    }
+    
+    // Set the OpenGL state after creating the context with SDL_SetVideoMode
+
+    glClearColor( 0, 0, 0, 0 );
+    
+#if !EMSCRIPTEN
+    glEnable( GL_TEXTURE_2D ); // Need this to display a texture XXX unnecessary in OpenGL ES 2.0/WebGL
+#endif
+
+    glViewport( 0, 0, 640, 480 );
+    
+    glMatrixMode( GL_MODELVIEW );
+    glLoadIdentity();
+    
+    // Clear the screen before drawing
+    glClear( GL_COLOR_BUFFER_BIT );
+    
+    typedef struct Vertex {
+        GLfloat x;
+        GLfloat y;
+    } Vertex;
+    
+    typedef struct Color {
+        GLubyte r;
+        GLubyte g;
+        GLubyte b;
+        GLubyte a;
+    } Color;
+    
+    Vertex vertices[3] = {
+        {-1.0, 0.0},
+        { 0.0, 1.0},
+        { 1.0, 0.0}
+    };
+    
+    Color colors[3] = {
+        {0xFF, 0x00, 0x00, 0xFF},
+        {0x00, 0xFF, 0x00, 0xFF},
+        {0x00, 0x00, 0xFF, 0xFF}
+    };
+    
+    Vertex vertices2[3] = {
+        {-1.0,  0.0},
+        { 1.0,  0.0},
+        { 0.0, -1.0}
+    };
+    
+    Color colors2[3] = {
+        {0xFF, 0x00, 0x00, 0xFF},
+        {0x00, 0x00, 0xFF, 0xFF},
+        {0x00, 0xFF, 0x00, 0xFF}
+    };
+    
+    // DRAW
+    
+    // Clear the screen before drawing
+    glClear( GL_COLOR_BUFFER_BIT );
+    
+    // This test ensures that we can use two separate arrays in memory for different
+    // attributes, and that they each can have different stride.
+    // The first test shows implicit striding (the zero indicates tightly packed)
+    // The second test shows explicit striding where the stride is passed in
+    //   even though it also is tightly packed
+    
+    glEnableClientState(GL_VERTEX_ARRAY);
+    glEnableClientState(GL_COLOR_ARRAY);
+
+    // TEST 1
+    
+    glVertexPointer(2, GL_FLOAT, 0, vertices);
+    glColorPointer(4, GL_UNSIGNED_BYTE, 0, colors);
+    glDrawArrays(GL_TRIANGLE_STRIP, 0, 3);
+    
+    // TEST 2
+    
+    glVertexPointer(2, GL_FLOAT, 8, vertices2);
+    glColorPointer(4, GL_UNSIGNED_BYTE, 4, colors2);
+    glDrawArrays(GL_TRIANGLE_STRIP, 0, 3);
+
+    glDisableClientState(GL_COLOR_ARRAY);
+    glDisableClientState(GL_VERTEX_ARRAY);
+
+    SDL_GL_SwapBuffers();
+    
+#if !EMSCRIPTEN
+    // Wait for 3 seconds to give us a chance to see the image
+    SDL_Delay(3000);
+#endif
+
+    SDL_Quit();
+    
+    return 0;
+}