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/*
* gldgCam.c
*
* OpenGL Graph Display camera control module implementation
*
* Written by: Shawn Taras
*/
#include <stdlib.h>
#include <math.h>
#include <gtk/gtk.h>
#include <gdk/gdkkeysyms.h>
#include <GL/gl.h>
#include <GL/glu.h>
#include "glgd.h"
/*
* Defines
*/
#define _PI (M_PI)
#define _DEG2RAD(x) ((x) * _PI / 180.0)
/*
* External public functions
*/
GLboolean
glgdCamInit(glgdCam *cam)
{
if (cam != NULL)
{
cam->flags = GLGDCAM_FLAG_INITIALIZED;
glgdMatrixIdentity(cam->projMtx);
glgdQuatIdentity(cam->camRot);
cam->camPos[0] = 0.0;
cam->camPos[1] = 0.0;
cam->camPos[2] = 0.0;
cam->mouseLast[0] = -1.0;
cam->mouseLast[1] = -1.0;
cam->tanFOV[0] = 0.414; /* 45 degree FOV */
cam->tanFOV[1] = 0.414;
cam->winDim[0] = 0.0;
cam->winDim[1] = 0.0;
return GL_TRUE;
}
return GL_FALSE;
}
GLboolean
glgdCamBegin(glgdCam *cam)
{
glgdMatrix camRotMtx;
if (cam)
{
/* Load the projection matrix */
glMatrixMode(GL_PROJECTION);
glLoadMatrixd(cam->projMtx);
/* Compute and load the modelview matrix */
glMatrixMode(GL_MODELVIEW);
glPushMatrix();
glLoadIdentity();
glTranslated(cam->camPos[0], cam->camPos[1], cam->camPos[2]);
glgdMatrixSetByQuat(camRotMtx, cam->camRot);
glMultMatrixd(camRotMtx);
return GL_TRUE;
}
return GL_FALSE;
}
GLboolean
glgdCamBeginPick(glgdCam *cam, GLdouble mx, GLdouble my)
{
GLint viewport[4];
glgdMatrix camRotMtx;
if (cam)
{
glGetIntegerv(GL_VIEWPORT, viewport);
/* Load the projection matrix */
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPickMatrix(mx, viewport[3] - my, 8.0, 8.0, viewport);
glMultMatrixd(cam->projMtx);
/* Compute and load the modelview matrix */
glMatrixMode(GL_MODELVIEW);
glPushMatrix();
glLoadIdentity();
glTranslated(cam->camPos[0], cam->camPos[1], cam->camPos[2]);
glgdMatrixSetByQuat(camRotMtx, cam->camRot);
glMultMatrixd(camRotMtx);
return GL_TRUE;
}
return GL_FALSE;
}
GLboolean
glgdCamUpdate(glgdCam *cam, glgdCamMode mode,
GLdouble mx, GLdouble my, GLdouble frameTime)
{
glgdQuat qa, qb, qc;
GLdouble scale;
GLdouble ratio[2];
GLdouble dx, dy;
GLboolean something;
if (frameTime <= 0.016667)
{
frameTime = 0.016667;
}
if (cam != NULL)
{
something = GL_FALSE;
if (mode == GLGDCAM_MODE_NONE)
{
cam->mouseLast[0] = -1.0;
cam->mouseLast[1] = -1.0;
}
else
{
if (cam->mouseLast[0] >= 0.0)
{
dx = mx - cam->mouseLast[0];
dy = my - cam->mouseLast[1];
if (mode == GLGDCAM_MODE_ORBIT)
{
scale = 10.0 * frameTime;
glgdQuatSetByXRotation(qa, _DEG2RAD(dy * scale));
glgdQuatSetByYRotation(qb, _DEG2RAD(dx * scale));
glgdQuatMult(qc, qb, cam->camRot);
glgdQuatMult(cam->camRot, qc, qa);
}
else if (mode == GLGDCAM_MODE_ZOOM)
{
scale = 10.0 * frameTime;
cam->camPos[2] += dx * scale;
}
else if (mode == GLGDCAM_MODE_PAN)
{
ratio[0] = cam->camPos[2]*cam->tanFOV[0]/cam->winDim[0];
ratio[1] = cam->camPos[2]*cam->tanFOV[1]/cam->winDim[1];
cam->camPos[0] -= dx * ratio[0];
cam->camPos[1] += dy * ratio[1];
}
}
cam->mouseLast[0] = mx;
cam->mouseLast[1] = my;
something = GL_TRUE;
}
return something;
}
return GL_FALSE;
}
GLboolean
glgdCamEnd(glgdCam *cam)
{
if (cam)
{
glMatrixMode(GL_MODELVIEW);
glPopMatrix();
return GL_TRUE;
}
return GL_FALSE;
}
GLboolean
glgdCamPosSet(glgdCam *cam, GLdouble x, GLdouble y, GLdouble z)
{
if (cam)
{
cam->camPos[0] = x;
cam->camPos[1] = y;
cam->camPos[2] = z;
return GL_TRUE;
}
return GL_FALSE;
}
GLboolean
glgdCamWinDimSet(glgdCam *cam, GLdouble w, GLdouble h)
{
if (cam)
{
cam->winDim[0] = w;
cam->winDim[1] = h;
return GL_TRUE;
}
return GL_FALSE;
}
GLboolean
glgdCamRotSet(glgdCam *cam, glgdQuat qrot)
{
if (cam)
{
return glgdQuatSet(cam->camRot, qrot);
}
return GL_FALSE;
}
GLboolean
glgdCamMouseSet(glgdCam *cam, GLdouble mx, GLdouble my)
{
if (cam)
{
cam->mouseLast[0] = mx;
cam->mouseLast[1] = my;
}
return GL_FALSE;
}
GLboolean
glgdCamFrameWidth(glgdCam *cam,
GLdouble left, GLdouble right,
GLdouble bottom, GLdouble top)
{
GLdouble z;
GLdouble w, h;
w = right - left;
h = top - bottom;
if (cam && w > 0.0 && h > 0.0)
{
cam->camPos[0] = -GLGD_HALF(left + right);
cam->camPos[1] = -GLGD_HALF(bottom + top);
cam->camPos[2] = -(w * 0.5) / tan(cam->tanFOV[0]);
return GL_TRUE;
}
return GL_FALSE;
}
GLboolean
glgdCamFrameHeight (glgdCam *cam,
GLdouble left, GLdouble right,
GLdouble bottom, GLdouble top)
{
GLdouble z;
GLdouble w, h;
w = right - left;
h = top - bottom;
if (cam && w > 0.0 && h > 0.0)
{
cam->camPos[0] = -GLGD_HALF(left + right);
cam->camPos[1] = -GLGD_HALF(bottom + top);
cam->camPos[2] = -(h * 0.5) / cam->tanFOV[1];
return GL_TRUE;
}
return GL_FALSE;
}
GLboolean
glgdCamFrame(glgdCam *cam,
GLdouble left, GLdouble right,
GLdouble bottom, GLdouble top)
{
GLdouble w, h;
w = right - left;
h = top - bottom;
if (cam && w > 0.0 && h > 0.0)
{
if (w > h)
{
glgdCamFrameWidth(cam, left, right, bottom, top);
}
else
{
glgdCamFrameHeight(cam, left, right, bottom, top);
}
glgdTrace(2, "(%g,%g,%g,%g) -> (%g,%g,%g)\n",
left, right, bottom, top,
cam->camPos[0], cam->camPos[1], cam->camPos[2]);
return GL_TRUE;
}
return GL_FALSE;
}
GLboolean
glgdCamPerspective(glgdCam *cam,
GLdouble fovy,
GLdouble aspect,
GLdouble zNear,
GLdouble zFar)
{
GLdouble fovyBy2;
glgdMatrixPerspective(cam->projMtx, fovy, aspect, zNear, zFar);
fovyBy2 = fovy * 0.5;
cam->tanFOV[0] = tan(fovyBy2 / aspect);
cam->tanFOV[1] = tan(fovyBy2);
return GL_FALSE;
}
GLboolean
glgdCamFrustum(glgdCam *cam,
GLdouble left,
GLdouble right,
GLdouble bottom,
GLdouble top,
GLdouble zNear,
GLdouble zFar)
{
GLdouble aspect;
GLdouble fovyBy2;
glgdMatrixFrustum(cam->projMtx, left, right, bottom, top, zNear, zFar);
aspect = (top - bottom) / (right - left);
fovyBy2 = atan2((top - bottom) * 0.5, zNear);
cam->tanFOV[0] = tan(fovyBy2 / aspect);
cam->tanFOV[1] = tan(fovyBy2);
return GL_FALSE;
}
GLboolean
glgdCamOrtho(glgdCam *cam,
GLdouble left,
GLdouble right,
GLdouble bottom,
GLdouble top,
GLdouble zNear,
GLdouble zFar)
{
glgdMatrixOrtho(cam->projMtx, left, right, bottom, top, zNear, zFar);
return GL_FALSE;
}
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