diff options
Diffstat (limited to 'progs/trivial/pgon-mode.c')
-rw-r--r-- | progs/trivial/pgon-mode.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/progs/trivial/pgon-mode.c b/progs/trivial/pgon-mode.c new file mode 100644 index 0000000000..db58638619 --- /dev/null +++ b/progs/trivial/pgon-mode.c @@ -0,0 +1,136 @@ +/** + * Test glPolygonMode. + * A tri-strip w/ two tris is drawn so that the first tri is front-facing + * but the second tri is back-facing. + * Set glPolygonMode differently for the front/back faces + * + */ + + +#include <stdio.h> +#include <stdlib.h> +#include <math.h> +#include <GL/glut.h> + +static int Win; +static GLfloat Zrot = 0; +static GLboolean FrontFillBackUnfilled = GL_TRUE; +static GLboolean Lines = GL_TRUE; + + +static void +Draw(void) +{ + glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + + if (FrontFillBackUnfilled) { + if (Lines) { + printf("FrontMode = FILL, BackMode = LINE\n"); + glPolygonMode(GL_BACK, GL_LINE); + } + else { + printf("FrontMode = FILL, BackMode = POINT\n"); + glPolygonMode(GL_BACK, GL_POINT); + } + glPolygonMode(GL_FRONT, GL_FILL); + } + else { + if (Lines) { + printf("FrontMode = LINE, BackMode = FILL\n"); + glPolygonMode(GL_FRONT, GL_LINE); + } + else { + printf("FrontMode = POINT, BackMode = FILL\n"); + glPolygonMode(GL_FRONT, GL_POINT); + } + glPolygonMode(GL_BACK, GL_FILL); + } + + glPushMatrix(); + glRotatef(Zrot, 0, 0, 1); + + glBegin(GL_TRIANGLE_STRIP); + glVertex2f(-1, 0); + glVertex2f( 1, 0); + glVertex2f(0, 1); + glVertex2f(0, -1); + glEnd(); + + glPopMatrix(); + + glutSwapBuffers(); +} + + +static void +Reshape(int width, int height) +{ + glViewport(0, 0, width, height); + glMatrixMode(GL_PROJECTION); + glLoadIdentity(); + glFrustum(-1.0, 1.0, -1.0, 1.0, 5.0, 25.0); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); + glTranslatef(0.0, 0.0, -15.0); +} + + +static void +Key(unsigned char key, int x, int y) +{ + const GLfloat step = 3.0; + (void) x; + (void) y; + switch (key) { + case 'p': + FrontFillBackUnfilled = !FrontFillBackUnfilled; + break; + case 'l': + Lines = !Lines; + break; + case 'z': + Zrot -= step; + break; + case 'Z': + Zrot += step; + break; + case 27: + glutDestroyWindow(Win); + exit(0); + break; + } + glutPostRedisplay(); +} + + +static void +Init(void) +{ + printf("GL_RENDERER = %s\n", (char*) glGetString(GL_RENDERER)); + + glLineWidth(3.0); + glPointSize(3.0); + + glColor4f(1, 1, 1, 0.8); + glEnable(GL_BLEND); + glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); + + printf("Press 'p' to toggle polygon mode\n"); +} + + +int +main(int argc, char *argv[]) +{ + glutInit(&argc, argv); + glutInitWindowPosition(0, 0); + glutInitWindowSize(400, 400); + glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH); + Win = glutCreateWindow(argv[0]); + glutReshapeFunc(Reshape); + glutKeyboardFunc(Key); + glutDisplayFunc(Draw); + Init(); + glutMainLoop(); + return 0; +} |