done

diff --git a/glpixels.c b/glpixels.c
index cae9499..e63476b 100644 (file)
--- a/glpixels.c
+++ b/glpixels.c
@@ -14,11 +14,15 @@ enum {
        NUM_MODES
 };
 
+static const char *modestr[] = { "GL_POINTS", "glDrawPixels", "textured quad",
+       "textured triangle"};
+
 int init(void);
 void display(void);
 void idle(void);
 void reshape(int x, int y);
 void keyb(unsigned char key, int x, int y);
+void change_mode(int m);
 
 int win_width, win_height;
 int max_xscroll, max_yscroll;
@@ -29,11 +33,15 @@ unsigned int img[IMG_W * IMG_H];
 float *varr, *carr;
 unsigned int vbo_pos, vbo_col;
 int varr_sz, carr_sz;
+unsigned int tex, quad, tri;
 
 int mode = MODE_POINTS;
 
 int have_vbo = 1;      /* TODO */
 
+unsigned int start_tm;
+unsigned int num_frames;
+
 
 int main(int argc, char **argv)
 {
@@ -42,6 +50,8 @@ int main(int argc, char **argv)
        glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
        glutCreateWindow("GL pixel drawing methods");
 
+       change_mode(mode);
+
        glutDisplayFunc(display);
        glutReshapeFunc(reshape);
        glutKeyboardFunc(keyb);
@@ -50,6 +60,8 @@ int main(int argc, char **argv)
        if(init() == -1) {
                return 1;
        }
+
+       start_tm = glutGet(GLUT_ELAPSED_TIME);
        glutMainLoop();
        return 0;
 }
@@ -59,7 +71,6 @@ int init(void)
 {
        int i, j, xor, r, g, b;
        unsigned int *ptr;
-       unsigned int tex;
        float *vptr;
 
        ptr = img;
@@ -82,7 +93,7 @@ int init(void)
        glBindTexture(GL_TEXTURE_2D, tex);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-       glTexImage2D(GL_TEXTURE_2D, 1, GL_RGBA, win_width, win_height, 1, GL_RGBA, GL_UNSIGNED_BYTE, 0);
+       glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, win_width, win_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);
 
        varr_sz = win_width * win_height * sizeof *varr * 2;
        if(!(varr = malloc(varr_sz))) {
@@ -114,6 +125,25 @@ int init(void)
                glBufferData(GL_ARRAY_BUFFER, carr_sz, 0, GL_STREAM_DRAW);
        }
 
+       quad = glGenLists(1);
+       glNewList(quad, GL_COMPILE);
+       glBegin(GL_QUADS);
+       glTexCoord2f(0, 0); glVertex2f(0, 0);
+       glTexCoord2f(1, 0); glVertex2f(1, 0);
+       glTexCoord2f(1, 1); glVertex2f(1, 1);
+       glTexCoord2f(0, 1); glVertex2f(0, 1);
+       glEnd();
+       glEndList();
+
+       tri = glGenLists(1);
+       glNewList(tri, GL_COMPILE);
+       glBegin(GL_TRIANGLES);
+       glTexCoord2f(0, 0); glVertex2f(0, 0);
+       glTexCoord2f(2, 0); glVertex2f(2, 0);
+       glTexCoord2f(0, 2); glVertex2f(0, 2);
+       glEnd();
+       glEndList();
+
        return 0;
 }
 
@@ -121,12 +151,16 @@ void display(void)
 {
        int i, j;
        unsigned int tm = glutGet(GLUT_ELAPSED_TIME);
+       unsigned int interv;
        float t = tm / 256.0f;
        int xoffs = (int)((sin(t) * 0.5f + 0.5f) * max_xscroll);
        int yoffs = (int)((cos(t) * 0.5f + 0.5f) * max_yscroll);
        unsigned int *start = img + yoffs * IMG_W + xoffs;
        float *vptr = varr;
 
+       glMatrixMode(GL_MODELVIEW);
+       glLoadIdentity();
+
        switch(mode) {
        case MODE_POINTS:
                /* draw with points */
@@ -171,16 +205,35 @@ void display(void)
                break;
 
        case MODE_TEXQUAD:
-               /* draw with textured quad */
-               break;
-
        case MODE_TEXTRI:
-               /* draw with textured triangle */
+               /* draw with textured quad or triangle */
+               glBindTexture(GL_TEXTURE_2D, tex);
+               glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, win_width, win_height, GL_RGBA,
+                               GL_UNSIGNED_BYTE, start);
+               glEnable(GL_TEXTURE_2D);
+               glScalef(win_width, win_height, 1);
+               glCallList(mode == MODE_TEXQUAD ? quad : tri);
+               glDisable(GL_TEXTURE_2D);
                break;
        }
 
        glutSwapBuffers();
        assert(glGetError() == GL_NO_ERROR);
+
+       tm = glutGet(GLUT_ELAPSED_TIME);
+       interv = tm - start_tm;
+       if(++num_frames == 1000 || interv > 5000) {
+               unsigned int fps = 100000 * num_frames / interv;
+               printf("%s: %.2f fps\n", modestr[mode], fps / 100.0f);
+               num_frames = 0;
+               start_tm = tm;
+
+               if(mode < NUM_MODES - 1) {
+                       change_mode(mode + 1);
+               } else {
+                       exit(0);
+               }
+       }
 }
 
 void idle(void)
@@ -211,10 +264,18 @@ void keyb(unsigned char key, int x, int y)
                exit(0);
 
        case ' ':
-               mode = (mode + 1) % NUM_MODES;
+               change_mode((mode + 1) % NUM_MODES);
                break;
 
        default:
                break;
        }
 }
+
+void change_mode(int m)
+{
+       char title[128];
+       mode = m;
+       sprintf(title, "GL pixel drawing test: %s\n", modestr[mode]);
+       glutSetWindowTitle(title);
+}