mkxp/src/glstate.cpp

140 lines
3.2 KiB
C++

/*
** glstate.cpp
**
** This file is part of mkxp.
**
** Copyright (C) 2013 Jonas Kulla <Nyocurio@gmail.com>
**
** mkxp 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 2 of the License, or
** (at your option) any later version.
**
** mkxp 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 mkxp. If not, see <http://www.gnu.org/licenses/>.
*/
#include "glstate.h"
#include "GL/glew.h"
#include "SDL2/SDL_rect.h"
#include "etc.h"
void GLClearColor::apply(const Vec4 &value)
{
glClearColor(value.x, value.y, value.z, value.w);
}
void GLScissorBox::apply(const IntRect &value)
{
glScissor(value.x, value.y, value.w, value.h);
}
void GLScissorBox::setIntersect(const IntRect &value)
{
IntRect &current = get();
SDL_Rect r1 = { current.x, current.y, current.w, current.h };
SDL_Rect r2 = { value.x, value.y, value.w, value.h };
SDL_Rect result;
if (!SDL_IntersectRect(&r1, &r2, &result))
result.w = result.h = 0;
set(IntRect(result.x, result.y, result.w, result.h));
}
void GLScissorTest::apply(const bool &value)
{
value ? glEnable(GL_SCISSOR_TEST) : glDisable(GL_SCISSOR_TEST);
}
void GLTexture2D::apply(const bool &value)
{
value ? glEnable(GL_TEXTURE_2D) : glDisable(GL_TEXTURE_2D);
}
void GLBlendMode::apply(const BlendType &value)
{
switch (value)
{
case BlendNone :
glBlendEquation(GL_FUNC_ADD);
glBlendFunc(GL_ONE, GL_ZERO);
break;
case BlendNormal :
glBlendEquation(GL_FUNC_ADD);
glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA,
GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
break;
case BlendAddition :
glBlendEquation(GL_FUNC_ADD);
glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE,
GL_ONE, GL_ONE);
break;
case BlendSubstraction :
// FIXME Alpha calculation is untested
glBlendEquation(GL_FUNC_REVERSE_SUBTRACT);
glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE,
GL_ONE, GL_ONE);
break;
}
}
void GLViewport::apply(const IntRect &value)
{
glViewport(value.x, value.y, value.w, value.h);
}
void GLState::setViewport(int width, int height)
{
viewport.set(IntRect(0, 0, width, height));
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0, width, 0, height, 0, 1);
glMatrixMode(GL_MODELVIEW);
}
void GLState::pushSetViewport(int width, int height)
{
viewport.pushSet(IntRect(0, 0, width, height));
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
glOrtho(0, width, 0, height, 0, 1);
glMatrixMode(GL_MODELVIEW);
}
void GLState::popViewport()
{
viewport.pop();
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);
}
GLState::Caps::Caps()
{
glGetIntegerv(GL_MAX_TEXTURE_SIZE, &maxTexSize);
}
GLState::GLState()
{
clearColor.init(Vec4(0, 0, 0, 1));
blendMode.init(BlendNormal);
scissorTest.init(false);
scissorBox.init(IntRect(0, 0, 640, 480));
texture2D.init(true);
}