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-rw-r--r--progs/tests/mapbufrange.c205
1 files changed, 205 insertions, 0 deletions
diff --git a/progs/tests/mapbufrange.c b/progs/tests/mapbufrange.c
new file mode 100644
index 0000000000..0021bb2607
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+++ b/progs/tests/mapbufrange.c
@@ -0,0 +1,205 @@
+/*
+ * Test glMapBuffer() and glMapBufferRange()
+ *
+ * Fill a VBO with vertex data to draw several colored quads.
+ * On each redraw, update the geometry for just one rect in the VBO.
+ *
+ * Brian Paul
+ * 4 March 2009
+ */
+
+
+#include <assert.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <GL/glew.h>
+#include <GL/glew.h>
+#include <GL/glut.h>
+
+static GLuint Win;
+static const GLuint NumRects = 10;
+static GLuint BufferID;
+static GLboolean Anim = GL_TRUE;
+static GLboolean UseBufferRange = GL_FALSE;
+
+
+
+static const float RectData[] = {
+ /* vertex */ /* color */
+ 0, -1, 0, 1, 0, 0,
+ 1, 0, 0, 1, 1, 0,
+ 0, 1, 0, 0, 1, 1,
+ -1, 0, 0, 1, 0, 1
+};
+
+
+/**
+ * The buffer contains vertex positions (float[3]) and colors (float[3])
+ * for 'NumRects' quads.
+ * This function updates/rotates one quad in the buffer.
+ */
+static void
+UpdateRect(int r, float angle)
+{
+ float *rect;
+ int i;
+
+ assert(r < NumRects);
+
+ glBindBufferARB(GL_ARRAY_BUFFER_ARB, BufferID);
+ if (UseBufferRange) {
+ GLintptr offset = r * sizeof(RectData);
+ GLsizeiptr length = sizeof(RectData);
+ GLbitfield access = GL_MAP_WRITE_BIT | GL_MAP_INVALIDATE_RANGE_BIT;
+ float *buf = (float *) glMapBufferRange(GL_ARRAY_BUFFER_ARB,
+ offset, length, access);
+ rect = buf;
+ }
+ else {
+ /* map whole buffer */
+ float *buf = (float *)
+ glMapBufferARB(GL_ARRAY_BUFFER_ARB, GL_WRITE_ONLY_ARB);
+ rect = buf + r * 24;
+ }
+
+ /* set rect verts/colors */
+ memcpy(rect, RectData, sizeof(RectData));
+
+ /* loop over four verts, updating vertices */
+ for (i = 0; i < 4; i++) {
+ float x = 0.2 * RectData[i*6+0];
+ float y = 0.2 * RectData[i*6+1];
+ float xpos = -2.5 + 0.5 * r;
+ float ypos = 0.0;
+
+ /* translate and rotate vert */
+ rect[i * 6 + 0] = xpos + x * cos(angle) + y * sin(angle);
+ rect[i * 6 + 1] = ypos + x * sin(angle) - y * cos(angle);
+ }
+
+ glUnmapBufferARB(GL_ARRAY_BUFFER_ARB);
+}
+
+
+static void
+LoadBuffer(void)
+{
+ static int frame = 0;
+ float angle = glutGet(GLUT_ELAPSED_TIME) * 0.001;
+ UpdateRect(frame % NumRects, angle);
+ frame++;
+}
+
+
+static void
+Draw(void)
+{
+ 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_QUADS, 0, NumRects * 4);
+
+ if (0)
+ glFinish();
+}
+
+
+static void
+Display(void)
+{
+ glClear(GL_COLOR_BUFFER_BIT);
+ Draw();
+ glutSwapBuffers();
+}
+
+
+static void
+Reshape(int width, int height)
+{
+ glViewport(0, 0, width, height);
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glOrtho(-3.0, 3.0, -1.0, 1.0, -1.0, 1.0);
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+}
+
+
+static void
+Idle(void)
+{
+ LoadBuffer();
+ glutPostRedisplay();
+}
+
+
+static void
+Key(unsigned char key, int x, int y)
+{
+ (void) x;
+ (void) y;
+ if (key == 'a') {
+ Anim = !Anim;
+ glutIdleFunc(Anim ? Idle : NULL);
+ }
+ else if (key == 's') {
+ LoadBuffer();
+ }
+ else if (key == 27) {
+ glutDestroyWindow(Win);
+ exit(0);
+ }
+ glutPostRedisplay();
+}
+
+
+static void
+Init(void)
+{
+ GLuint BufferSize = NumRects * sizeof(RectData);
+ float *buf;
+
+ if (!glutExtensionSupported("GL_ARB_vertex_buffer_object")) {
+ printf("GL_ARB_vertex_buffer_object not found!\n");
+ exit(0);
+ }
+
+ UseBufferRange = glutExtensionSupported("GL_ARB_map_buffer_range");
+ printf("Use GL_ARB_map_buffer_range: %c\n", "NY"[UseBufferRange]);
+
+ printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
+
+ /* initially load buffer with zeros */
+ buf = (float *) calloc(1, BufferSize);
+
+ glGenBuffersARB(1, &BufferID);
+ glBindBufferARB(GL_ARRAY_BUFFER_ARB, BufferID);
+ glBufferDataARB(GL_ARRAY_BUFFER_ARB, BufferSize, buf, GL_DYNAMIC_DRAW_ARB);
+
+ free(buf);
+}
+
+
+int
+main(int argc, char *argv[])
+{
+ glutInit(&argc, argv);
+ glutInitWindowSize(800, 200);
+ glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
+ Win = glutCreateWindow(argv[0]);
+ glewInit();
+ glewInit();
+ glutReshapeFunc(Reshape);
+ glutKeyboardFunc(Key);
+ glutDisplayFunc(Display);
+ glutIdleFunc(Anim ? Idle : NULL);
+ Init();
+ glutMainLoop();
+ return 0;
+}