diff options
| -rw-r--r-- | progs/tests/Makefile | 1 | ||||
| -rw-r--r-- | progs/tests/SConscript | 1 | ||||
| -rw-r--r-- | progs/tests/persp_hint.c | 149 |
3 files changed, 151 insertions, 0 deletions
diff --git a/progs/tests/Makefile b/progs/tests/Makefile index f3f1aea944..23fe3c35c1 100644 --- a/progs/tests/Makefile +++ b/progs/tests/Makefile @@ -67,6 +67,7 @@ SOURCES = \ no_s3tc.c \ packedpixels.c \ pbo.c \ + persp_hint.c \ prog_parameter.c \ quads.c \ random.c \ diff --git a/progs/tests/SConscript b/progs/tests/SConscript index 9d89ff6a0d..9e3a646f80 100644 --- a/progs/tests/SConscript +++ b/progs/tests/SConscript @@ -90,6 +90,7 @@ progs = [ 'no_s3tc', 'packedpixels', 'pbo', + 'persp_hint', 'prog_parameter', 'quads', 'random', diff --git a/progs/tests/persp_hint.c b/progs/tests/persp_hint.c new file mode 100644 index 0000000000..27140d1f56 --- /dev/null +++ b/progs/tests/persp_hint.c @@ -0,0 +1,149 @@ +/* + * Test the GL_PERSPECTIVE_CORRECTION_HINT setting and its effect on + * color interpolation. + * + * Press 'i' to toggle between GL_NICEST/GL_FASTEST/GL_DONT_CARE. + * + * Depending on the driver, the hint may make a difference, or not. + */ + + +#include <stdlib.h> +#include <stdio.h> +#include <GL/glut.h> + + +static GLenum PerspHint = GL_DONT_CARE; + + +static void +init(void) +{ + GLubyte image[256][256][4]; + GLuint i, j; + for (i = 0; i < 256; i++) { + for (j = 0; j < 256; j++) { + image[i][j][0] = j; + image[i][j][1] = j; + image[i][j][2] = j; + image[i][j][3] = 255; + } + } + glTexImage2D(GL_TEXTURE_2D, 0, 4, 256, 256, 0, + GL_RGBA, GL_UNSIGNED_BYTE, image); + glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); + glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); + glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); + glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); + glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL); + + printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER)); +} + + +static void +display(void) +{ + switch (PerspHint) { + case GL_NICEST: + printf("hint = GL_NICEST\n"); + break; + case GL_FASTEST: + printf("hint = GL_FASTEST\n"); + break; + case GL_DONT_CARE: + printf("hint = GL_DONT_CARE\n"); + break; + default: + ; + } + + glClear(GL_COLOR_BUFFER_BIT); + +#if 1 + glBegin(GL_QUADS); + /* exercise perspective interpolation */ + glColor3f(0.0, 0.0, 0.0); glVertex3f(-1.0, -1.0, -1.0); + glColor3f(0.0, 0.0, 0.0); glVertex3f(-1.0, 1.0, -1.0); + glColor3f(0.0, 1.0, 0.0); glVertex3f( 7.0, 1.0, -7.0); + glColor3f(0.0, 1.0, 0.0); glVertex3f( 7.0, -1.0, -7.0); + + /* stripe of linear interpolation */ + glColor3f(0.0, 0.0, 0.0); glVertex3f(-1.0, -0.1, -1.001); + glColor3f(0.0, 0.0, 0.0); glVertex3f(-1.0, 0.1, -1.001); + glColor3f(0.0, 1.0, 0.0); glVertex3f( 1.0, 0.1, -1.001); + glColor3f(0.0, 1.0, 0.0); glVertex3f( 1.0, -0.1, -1.001); + glEnd(); +#else + glEnable(GL_TEXTURE_2D); + glBegin(GL_QUADS); + glTexCoord2f(0.0, 0.0); glVertex3f(-1.0, 0.0, -1.0); + glTexCoord2f(0.0, 1.0); glVertex3f(-1.0, 1.0, -1.0); + glTexCoord2f(1.0, 1.0); glVertex3f( 5.0, 1.0, -7.0); + glTexCoord2f(1.0, 0.0); glVertex3f( 5.0, 0.0, -7.0); + + glTexCoord2f(0.0, 0.0); glVertex3f(-1.0, -1.0, -1.001); + glTexCoord2f(0.0, 1.0); glVertex3f(-1.0, 0.0, -1.001); + glTexCoord2f(1.0, 1.0); glVertex3f( 1.0, 0.0, -1.001); + glTexCoord2f(1.0, 0.0); glVertex3f( 1.0, -1.0, -1.001); + glEnd(); +#endif + + glFlush(); +} + + +static void +reshape(int w, int h) +{ + glViewport(0, 0, w, h); + glMatrixMode(GL_PROJECTION); + glLoadIdentity(); + gluPerspective(90.0, (GLfloat) w / h, 1.0, 300.0); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); +} + + +static void +key(unsigned char k, int x, int y) +{ + switch (k) { + case 27: /* Escape */ + exit(0); + break; + case 'i': + if (PerspHint == GL_FASTEST) + PerspHint = GL_NICEST; + else if (PerspHint == GL_NICEST) + PerspHint = GL_DONT_CARE; + else + PerspHint = GL_FASTEST; + glHint(GL_PERSPECTIVE_CORRECTION_HINT, PerspHint); + break; + default: + return; + } + glutPostRedisplay(); +} + + +int +main(int argc, char** argv) +{ + glutInit(&argc, argv); + glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB); + glutInitWindowSize (500, 500); + glutCreateWindow (argv[0]); + glutReshapeFunc (reshape); + glutDisplayFunc(display); + glutKeyboardFunc(key); + + printf("Main quad: perspective projection\n"); + printf("Middle stripe: linear interpolation\n"); + printf("Press 'i' to toggle interpolation hint\n"); + init(); + + glutMainLoop(); + return 0; +} |