scummvm/engines/stark/gfx/opengl.cpp

150 lines
3.7 KiB
C++

/* Residual - A 3D game interpreter
*
* Residual is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the AUTHORS
* file distributed with this source distribution.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
* This library 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
* Lesser General Public License for more details.
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*
* $URL$
* $Id$
*
*/
#include "engines/stark/gfx/opengl.h"
#include "common/system.h"
#include "graphics/pixelbuffer.h"
#include "math/matrix4.h"
#ifdef USE_OPENGL
#ifdef SDL_BACKEND
#include <SDL_opengl.h>
#else
#include <GL/gl.h>
//#include <GL/glu.h>
#endif
namespace Stark {
OpenGLGfxDriver::OpenGLGfxDriver() {
}
OpenGLGfxDriver::~OpenGLGfxDriver() {
}
void OpenGLGfxDriver::setupScreen(int screenW, int screenH, bool fullscreen) {
g_system->setupScreen(screenW, screenH, fullscreen, true);
_screenWidth = screenW;
_screenHeight = screenH;
}
void OpenGLGfxDriver::setGameViewport() {
glViewport(0, _screenHeight - kGameViewportHeight - kTopBorderHeight, _screenWidth, kGameViewportHeight);
}
void OpenGLGfxDriver::setupPerspective(const Math::Matrix4 &projectionMatrix) {
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glMultMatrixf(projectionMatrix.getData());
}
void OpenGLGfxDriver::setupCamera(const Math::Vector3d &position, const Math::Matrix4 &lookAt) {
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glMultMatrixf(lookAt.getData());
glTranslatef(-position.x(), -position.y(), -position.z());
}
void OpenGLGfxDriver::clearScreen() {
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
}
void OpenGLGfxDriver::flipBuffer() {
g_system->updateScreen();
}
void OpenGLGfxDriver::drawSurface(const Graphics::Surface *surface, Common::Point dest, Common::Rect rect) {
// Draw the whole surface by default
if (rect.isEmpty())
rect = Common::Rect(surface->w, surface->h);
start2DMode();
glDisable(GL_TEXTURE_2D);
glRasterPos2f(-1.0, 1.0);
glBitmap(0, 0, 0, 0, dest.x, -dest.y, nullptr);
glDrawPixels(surface->w, surface->h, GL_RGBA, GL_UNSIGNED_BYTE, surface->getPixels());
end2DMode();
}
void OpenGLGfxDriver::start2DMode() {
// Load the ModelView matrix with the identity
glMatrixMode(GL_MODELVIEW);
glPushMatrix();
glLoadIdentity();
// Load the Projection matrix with the identity
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
// Enable alpha blending
glEnable(GL_BLEND);
//glBlendEquation(GL_FUNC_ADD); // It's the default
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glDepthMask(GL_FALSE);
// Flip the Y component
glPixelZoom(1.0f, -1.0f);
// Required by RGB sources, but not by RGBA
//glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
}
void OpenGLGfxDriver::end2DMode() {
// Disable alpha blending
glDisable(GL_BLEND);
glDepthMask(GL_TRUE);
// Pop the identity Projection matrix
glMatrixMode(GL_PROJECTION);
glPopMatrix();
// Pop the identity ModelView matrix
glMatrixMode(GL_MODELVIEW);
glPopMatrix();
}
void OpenGLGfxDriver::set3DMode() {
glMatrixMode(GL_MODELVIEW);
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LESS);
}
} // End of namespace Stark
#endif // USE_OPENGL