Initial commit.

grGL currently generates and shows a random graph of 1000 nodes
with 6000 edges as well as a red box as an example of OpenGL
drawing operations.

1 files changed, 155 insertions, 0 deletions

diff --git a/src/glancillary.c b/src/glancillary.c
new file mode 100644
index 0000000..959cdac
--- /dev/null
+++ b/src/glancillary.c
@@ -0,0 +1,155 @@
+#include <GL/gl.h>
+#include <GL/glu.h>
+
+#include "glancillary.h"
+
+
+
+/****************************
+ * GL init
+ ***************************/
+
+void glaInit(void)
+{
+  glClearColor(0.0, 0.0, 0.0, 0.0);
+  glShadeModel(GL_FLAT);
+  //glShadeModel(GL_SMOOTH);
+
+  glEnable(GL_BLEND);
+  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
+  // Init Model/view transformation
+  glMatrixMode(GL_MODELVIEW);
+
+  // Reset MV matrix
+  glLoadIdentity();
+}
+
+
+
+
+/****************************
+ * GL camera simulation helpers
+ ***************************/
+
+void glaCameraRotatef(GLfloat *cmat, GLfloat angle, GLfloat x, GLfloat y, GLfloat z)
+{
+  glPushMatrix();
+    glLoadIdentity();
+    glRotatef(angle, x, y, z);
+    glMultMatrixf(cmat);
+    glGetFloatv(GL_MODELVIEW_MATRIX, cmat);
+  glPopMatrix();
+}
+
+void glaCameraTranslatef(GLfloat *cmat, GLfloat x, GLfloat y, GLfloat z)
+{
+  glPushMatrix();
+    glLoadIdentity();
+    glTranslatef(x, y, z);
+    glMultMatrixf(cmat);
+    glGetFloatv(GL_MODELVIEW_MATRIX, cmat);
+  glPopMatrix();
+}
+
+
+
+
+/****************************
+ * GL box drawing example
+ ***************************/
+
+void glaDrawExample(void)
+{
+  // Draw the corner dots
+  glPointSize(5.0);
+  glColor3f(1.0, 1.0, 0.0);
+  glBegin(GL_POINTS);
+    glVertex3f(-1.0, -1.0, -1.0);
+    glVertex3f(1.0, -1.0, -1.0);
+    glVertex3f(1.0, 1.0, -1.0);
+    glVertex3f(-1.0, 1.0, -1.0);
+    glVertex3f(-1.0, -1.0, -1.0);
+    glVertex3f(-1.0, -1.0, 1.0);
+    glVertex3f(-1.0, 1.0, 1.0);
+  glEnd();
+
+  // Draw a line with fixed vertices
+  glColor3f(0.5, 1.0, 0.5);
+  glBegin(GL_LINE_STRIP);
+    glVertex3f(0.0, 0.0, 0.0);
+    glVertex3f(0.0, 0.5, 0.0);
+    glVertex3f(0.5, 0.5, 0.5);
+  glEnd();
+
+  // Draw the box boundaries
+  glColor3f(1.0, 0.0, 0.0);
+  glBegin(GL_LINE_STRIP);
+    glVertex3f(-1.0, -1.0, -1.0);
+    glVertex3f(1.0, -1.0, -1.0);
+    glVertex3f(1.0, 1.0, -1.0);
+    glVertex3f(-1.0, 1.0, -1.0);
+    glVertex3f(-1.0, -1.0, -1.0);
+    glVertex3f(-1.0, -1.0, 1.0);
+    glVertex3f(-1.0, 1.0, 1.0);
+    glVertex3f(-1.0, 1.0, -1.0);
+  glEnd();
+}
+
+
+
+
+
+
+
+
+
+
+/****************************
+ * GL selection (currently defunct)
+ ***************************/
+
+// Selection helper, currently defunct.
+void glaSelect(int x, int y)
+{
+  int i;
+  GLuint namebuf[64] = {0};
+  GLint hits, view[4];
+  GLfloat projmat[16];
+
+  // Account for inverse Y coordinate
+  glGetIntegerv(GL_VIEWPORT, view);
+  y = view[3] - y;
+
+  glSelectBuffer(64, namebuf);
+  glRenderMode(GL_SELECT);
+
+  // Reset name stack
+  glInitNames();
+  glPushName(0);
+
+  // Restrict projection matrix to selection area
+  glGetFloatv(GL_PROJECTION_MATRIX, projmat);
+  glMatrixMode(GL_PROJECTION);
+  glPushMatrix();
+    glLoadIdentity();
+    gluPickMatrix(x, y, 1.0, 1.0, view);
+    glMultMatrixf(projmat);
+
+    // Redraw points to fill selection buffer
+    glMatrixMode(GL_MODELVIEW);
+    //glutSwapBuffers();
+    //drawPoints();
+
+    // Reset projection
+  glMatrixMode(GL_PROJECTION);
+  glPopMatrix();
+
+  hits = glRenderMode(GL_RENDER);
+
+  for (i = 0; i < hits; i++)
+    // Do something with the namebuf element here
+    break;
+
+  glMatrixMode(GL_MODELVIEW);
+}