gldraw.cpp

/*
 *  LDForge: LDraw parts authoring CAD
 *  Copyright (C) 2013 Santeri `arezey` Piippo
 *  
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *  
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *  
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <QtGui>
#include <QGLWidget>
#include <GL/glu.h>
#include "common.h"
#include "file.h"
#include "gldraw.h"
#include "bbox.h"
#include "colors.h"

#define GL_VERTEX(V) glVertex3d (V.x + g_faObjectOffset[0], \
	V.y + g_faObjectOffset[1], V.z + g_faObjectOffset[2]);

double g_faObjectOffset[3];

// =============================================================================
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// =============================================================================
renderer::renderer (QWidget* parent) {
	parent = parent; // shhh, GCC
	fRotX = fRotY = fRotZ = 0.0;
	fZoom = 1.0;
}

// =============================================================================
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// =============================================================================
void renderer::initializeGL () {
	glLoadIdentity();
	glMatrixMode (GL_MODELVIEW);
	
	setColor (gl_bgcolor.value, &glClearColor);
	
	glEnable (GL_POLYGON_OFFSET_FILL);
	glPolygonOffset (1.0f, 1.0f);
	
	glEnable (GL_DEPTH_TEST);
	glShadeModel (GL_SMOOTH);
	glEnable (GL_MULTISAMPLE);
	
	glEnable (GL_DITHER);
	glEnable (GL_BLEND);
	glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
	
	glEnable (GL_LINE_SMOOTH);
	glHint (GL_LINE_SMOOTH_HINT, GL_NICEST);
	glLineWidth (gl_linethickness);
	
	setMouseTracking (true);
	
	compileObjects ();
}

// =============================================================================
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// =============================================================================
void renderer::setColor (str zColor,
	void (*func) (float, float, float, float))
{
	QColor col (zColor.chars());
	
	if (!col.isValid ())
		return;
	
	(*func) (
		((double)col.red()) / 255.0f,
		((double)col.green()) / 255.0f,
		((double)col.blue()) / 255.0f,
		1.0f);
}

void renderer::setObjectColor (LDObject* obj, bool bBack) {
	if (gl_colorbfc &&
		obj->getType () != OBJ_Line &&
		obj->getType () != OBJ_CondLine)
	{
		if (bBack)
			glColor4f (0.9f, 0.0f, 0.0f, 1.0f);
		else
			glColor4f (0.0f, 0.8f, 0.0f, 1.0f);
		return;
	}
	
	if (obj->dColor == dMainColor)
		setColor (gl_maincolor, glColor4f);
	else {
		color* col = g_LDColors[obj->dColor];
		QColor qCol (col->zColor.chars());
		
		if (qCol.isValid ())
			glColor4f (
				((double)qCol.red()) / 255.0f,
				((double)qCol.green()) / 255.0f,
				((double)qCol.blue()) / 255.0f,
				col->fAlpha);
	}
}

// =============================================================================
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// =============================================================================
void renderer::hardRefresh () {
	compileObjects ();
	paintGL ();
	swapBuffers ();
	
	glLineWidth (gl_linethickness);
}

// =============================================================================
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// =============================================================================
void renderer::resizeGL (int w, int h) {
	glViewport (0, 0, w, h);
	glLoadIdentity ();
	glMatrixMode (GL_PROJECTION);
	gluPerspective (45.0f, (double)w / (double)h, 0.1f, 100.0f);
}

// =============================================================================
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// =============================================================================
void renderer::paintGL () {
	glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glMatrixMode (GL_MODELVIEW);
	
	glPushMatrix ();
		glLoadIdentity ();
		
		glTranslatef (
			(g_BBox.v0.x + g_BBox.v1.x) / -2.0,
			(g_BBox.v0.y + g_BBox.v1.y) / -2.0,
			(g_BBox.v0.z + g_BBox.v1.z) / -2.0
		);
		
		glTranslatef (0.0f, 0.0f, -5.0f);
		glTranslatef (0.0f, 0.0f, -fZoom);
		
		glRotatef (fRotX, 1.0f, 0.0f, 0.0f);
		glRotatef (fRotY, 0.0f, 1.0f, 0.0f);
		glRotatef (fRotZ, 0.0f, 0.0f, 1.0f);
		
		if (gl_colorbfc) {
			glEnable (GL_CULL_FACE);
			
			glCullFace (GL_FRONT);
			glCallList (uObjList);
			
			glCullFace (GL_BACK);
			glCallList (uObjListBack);
			
			glDisable (GL_CULL_FACE);
		} else
			glCallList (uObjList);
	glPopMatrix ();
}

// =============================================================================
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// =============================================================================
void renderer::compileObjects () {
	
	g_faObjectOffset[0] = -(g_BBox.v0.x + g_BBox.v1.x) / 2;
	g_faObjectOffset[1] = -(g_BBox.v0.y + g_BBox.v1.y) / 2;
	g_faObjectOffset[2] = -(g_BBox.v0.z + g_BBox.v1.z) / 2;
	
	if (!g_CurrentFile) {
		printf ("renderer: no files loaded, cannot compile anything\n");
		return;
	}
	
	GLuint* upaLists[2] = {
		&uObjList,
		&uObjListBack,
	};
	
	for (uchar j = 0; j < 2; ++j) {
		if (j && !gl_colorbfc)
			continue;
		
		*upaLists[j] = glGenLists (1);
		glNewList (*upaLists[j], GL_COMPILE);
		
		for (ulong i = 0; i < g_CurrentFile->objects.size(); i++)
			compileOneObject (g_CurrentFile->objects[i], j);
		
		glEndList ();
	}
}

// =============================================================================
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// =============================================================================
void renderer::compileOneObject (LDObject* obj, bool bBack) {
	if (!obj)
		return;
	
	switch (obj->getType ()) {
	case OBJ_Line:
		{
			setObjectColor (obj, bBack);
			
			// draw lines
			LDLine* line = static_cast<LDLine*> (obj);
			glBegin (GL_LINES);
			for (short i = 0; i < 2; ++i)
				GL_VERTEX (line->vaCoords[i])
			glEnd ();
		}
		break;
	
	case OBJ_CondLine:
		{
			glLineStipple (1, 0x6666);
			glEnable (GL_LINE_STIPPLE);
			
			setObjectColor (obj, bBack);
			LDCondLine* line = static_cast<LDCondLine*> (obj);
			
			glBegin (GL_LINES);
			for (short i = 0; i < 2; ++i)
				GL_VERTEX (line->vaCoords[i])
			glEnd ();
			
			glDisable (GL_LINE_STIPPLE);
		}
		break;
	
	case OBJ_Triangle:
		{
			LDTriangle* tri = static_cast<LDTriangle*> (obj);
			setObjectColor (obj, bBack);
			glBegin (GL_TRIANGLES);
			for (short i = 0; i < 3; ++i)
				GL_VERTEX (tri->vaCoords[i])
			glEnd ();
		}
		break;
		
	case OBJ_Quad:
		{
			LDQuad* quad = static_cast<LDQuad*> (obj);
			setObjectColor (obj, bBack);
			glBegin (GL_QUADS);
			for (short i = 0; i < 4; ++i)
				GL_VERTEX (quad->vaCoords[i])
			glEnd ();
		}
		break;
	
	default:
		break;
	}
}

// =============================================================================
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// =============================================================================
void renderer::clampAngle (double& fAngle) {
	while (fAngle < 0)
		fAngle += 360.0;
	while (fAngle > 360.0)
		fAngle -= 360.0;
}

// =============================================================================
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// =============================================================================
void renderer::mouseMoveEvent (QMouseEvent *event) {
	int dx = event->x () - lastPos.x ();
	int dy = event->y () - lastPos.y ();
	
	if (event->buttons () & Qt::LeftButton) {
		fRotX = fRotX + (dy);
		fRotY = fRotY + (dx);
		clampAngle (fRotX);
		clampAngle (fRotY);
	}
	
	if (event->buttons () & Qt::RightButton) {
		fRotX = fRotX + (dy);
		fRotZ = fRotZ + (dx);
		clampAngle (fRotX);
		clampAngle (fRotZ);
	}
	
	if (event->buttons () & Qt::MidButton) {
		fZoom += (dy / 100.0);
		fZoom = clamp (fZoom, 0.01, 100.0);
	}
	
	lastPos = event->pos();
	updateGL ();
}