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Diffstat (limited to 'progs/tests/mapvbo.c')
-rw-r--r-- | progs/tests/mapvbo.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/progs/tests/mapvbo.c b/progs/tests/mapvbo.c new file mode 100644 index 00000000000..c392e768358 --- /dev/null +++ b/progs/tests/mapvbo.c @@ -0,0 +1,139 @@ +/* + * Test glMapBuffer() call immediately after glDrawArrays(). + * See details below. + * + * NOTE: Do not use freeglut with this test! It calls the Display() + * callback twice right away instead of just once. + * + * Brian Paul + * 27 Feb 2009 + */ + + +#include <stdio.h> +#include <stdlib.h> +#include <GL/glew.h> +#include <GL/glut.h> + +static GLuint BufferID; + + +static GLuint Win; + + + + +/* + * Create VBO (position and color) and load with data. + */ +static void +SetupBuffers(void) +{ + static const GLfloat data[] = { + /* vertex */ /* color */ + 0, -1, 0, 1, 1, 0, + 1, 0, 0, 1, 1, 0, + 0, 1, 0, 1, 1, 0, + -1, 0, 0, 1, 1, 0 + }; + + glGenBuffersARB(1, &BufferID); + glBindBufferARB(GL_ARRAY_BUFFER_ARB, BufferID); + glBufferDataARB(GL_ARRAY_BUFFER_ARB, sizeof(data), data, + GL_STATIC_DRAW_ARB); +} + + +static void +Draw(void) +{ + static int count = 1; + + printf("Draw Frame %d\n", count); + count++; + + glBindBufferARB(GL_ARRAY_BUFFER_ARB, BufferID); + glVertexPointer(3, GL_FLOAT, 24, 0); + glEnable(GL_VERTEX_ARRAY); + + glColorPointer(3, GL_FLOAT, 24, (void*) 12); + glEnable(GL_COLOR_ARRAY); + + glDrawArrays(GL_TRIANGLE_FAN, 0, 4); + + if (0) + glFinish(); + + /* Immediately map the color buffer and change something. + * This should not effect the first glDrawArrays above, but the + * next time we draw we should see a black vertex. + */ + if (1) { + GLfloat *m = (GLfloat *) glMapBufferARB(GL_ARRAY_BUFFER_ARB, + GL_WRITE_ONLY_ARB); + m[3] = m[4] = m[5] = 0.0f; /* black vertex */ + glUnmapBufferARB(GL_ARRAY_BUFFER_ARB); + } +} + + +static void Display( void ) +{ + glClear( GL_COLOR_BUFFER_BIT ); + Draw(); + glutSwapBuffers(); +} + + +static void Reshape( int width, int height ) +{ + float ar = (float) width / (float) height; + glViewport( 0, 0, width, height ); + glMatrixMode( GL_PROJECTION ); + glLoadIdentity(); + glFrustum( -ar, ar, -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 ) +{ + (void) x; + (void) y; + if (key == 27) { + glutDestroyWindow(Win); + exit(0); + } + glutPostRedisplay(); +} + + +static void Init( void ) +{ + if (!glutExtensionSupported("GL_ARB_vertex_buffer_object")) { + printf("GL_ARB_vertex_buffer_object not found!\n"); + exit(0); + } + printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER)); + + SetupBuffers(); +} + + +int main( int argc, char *argv[] ) +{ + glutInit( &argc, argv ); + glutInitWindowPosition( 0, 0 ); + glutInitWindowSize( 300, 300 ); + glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE ); + Win = glutCreateWindow(argv[0]); + glewInit(); + glutReshapeFunc( Reshape ); + glutKeyboardFunc( Key ); + glutDisplayFunc( Display ); + Init(); + glutMainLoop(); + return 0; +} |