From 0a826921546612bee475ae240e0110977326bec1 Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Thu, 14 Jan 2010 09:21:18 -0700 Subject: progs/trivial: test glPolygonMode(POINT/LINE) with frustum clipping Note whether the new verts introduced by clipping show up as points and lines along the edge of the window... --- progs/trivial/tri-point-line-clipped.c | 91 ++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 progs/trivial/tri-point-line-clipped.c (limited to 'progs/trivial/tri-point-line-clipped.c') diff --git a/progs/trivial/tri-point-line-clipped.c b/progs/trivial/tri-point-line-clipped.c new file mode 100644 index 0000000000..eef926c24c --- /dev/null +++ b/progs/trivial/tri-point-line-clipped.c @@ -0,0 +1,91 @@ +/** + * Test frustum clipping w/ glPolygonMode LINE/POINT. + */ + +#include +#include +#include + + +static int win; + + +static void +Tri(void) +{ + glBegin(GL_TRIANGLES); + glColor3f(1, 0, 0); glVertex3f(-1.5, -0.8, 0.0); + glColor3f(0, 1, 0); glVertex3f( 1.5, -0.8, 0.0); + glColor3f(0, 0, 1); glVertex3f( 0.0, 0.9, 0.0); + glEnd(); +} + + +static void +Draw(void) +{ + glPointSize(13.0); + glLineWidth(5.0); + + glClear(GL_COLOR_BUFFER_BIT); + + glPolygonMode(GL_FRONT_AND_BACK, GL_LINE); + Tri(); + + glPolygonMode(GL_FRONT_AND_BACK, GL_POINT); + Tri(); + + glutSwapBuffers(); +} + + +static void Reshape(int width, int height) +{ + glViewport(0, 0, (GLint)width, (GLint)height); + glMatrixMode(GL_PROJECTION); + glLoadIdentity(); + glOrtho(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0); + glMatrixMode(GL_MODELVIEW); +} + + +static void +Key(unsigned char key, int x, int y) +{ + if (key == 27) { + glutDestroyWindow(win); + exit(0); + } + else { + glutPostRedisplay(); + } +} + + +static void +Init(void) +{ + fprintf(stderr, "GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER)); + fprintf(stderr, "GL_VERSION = %s\n", (char *) glGetString(GL_VERSION)); + fprintf(stderr, "GL_VENDOR = %s\n", (char *) glGetString(GL_VENDOR)); + fflush(stderr); +} + + +int +main(int argc, char **argv) +{ + glutInitWindowSize(300, 300); + glutInit(&argc, argv); + glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH); + win = glutCreateWindow(*argv); + if (!win) { + return 1; + } + Init(); + glutReshapeFunc(Reshape); + glutKeyboardFunc(Key); + glutDisplayFunc(Draw); + glutMainLoop(); + return 0; +} -- cgit v1.2.3 From 7fcfb7193107f192bcadccd50115a5216f98d567 Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Thu, 14 Jan 2010 09:38:47 -0700 Subject: progs/trivial: test user clip plane in tri-point-line-clipped.c --- progs/trivial/tri-point-line-clipped.c | 35 +++++++++++++++++++++++++++++----- 1 file changed, 30 insertions(+), 5 deletions(-) (limited to 'progs/trivial/tri-point-line-clipped.c') diff --git a/progs/trivial/tri-point-line-clipped.c b/progs/trivial/tri-point-line-clipped.c index eef926c24c..f8c1015f5f 100644 --- a/progs/trivial/tri-point-line-clipped.c +++ b/progs/trivial/tri-point-line-clipped.c @@ -1,5 +1,10 @@ /** - * Test frustum clipping w/ glPolygonMode LINE/POINT. + * Test frustum/user clipping w/ glPolygonMode LINE/POINT. + * + * The bottom/left and bottom/right verts are outside the frustum and clipped. + * The top vertex is clipped by a user clipping plane. + * + * A filled gray reference triangle is shown underneath the points/lines. */ #include @@ -11,7 +16,7 @@ static int win; static void -Tri(void) +ColorTri(void) { glBegin(GL_TRIANGLES); glColor3f(1, 0, 0); glVertex3f(-1.5, -0.8, 0.0); @@ -21,19 +26,39 @@ Tri(void) } +static void +GrayTri(void) +{ + glColor3f(0.3, 0.3, 0.3); + glBegin(GL_TRIANGLES); + glVertex3f(-1.5, -0.8, 0.0); + glVertex3f( 1.5, -0.8, 0.0); + glVertex3f( 0.0, 0.9, 0.0); + glEnd(); +} + + static void Draw(void) { + static const GLdouble plane[4] = { 0, -1.0, 0, 0.5 }; + + glClear(GL_COLOR_BUFFER_BIT); + glPointSize(13.0); glLineWidth(5.0); - glClear(GL_COLOR_BUFFER_BIT); + glClipPlane(GL_CLIP_PLANE0, plane); + glEnable(GL_CLIP_PLANE0); + + glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); + GrayTri(); glPolygonMode(GL_FRONT_AND_BACK, GL_LINE); - Tri(); + ColorTri(); glPolygonMode(GL_FRONT_AND_BACK, GL_POINT); - Tri(); + ColorTri(); glutSwapBuffers(); } -- cgit v1.2.3