warzone2100/lib/ivis_opengl/piestate.c

227 lines
5.5 KiB
C

/*
This file is part of Warzone 2100.
Copyright (C) 1999-2004 Eidos Interactive
Copyright (C) 2005-2007 Warzone Resurrection Project
Warzone 2100 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.
Warzone 2100 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 Warzone 2100; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/***************************************************************************/
/*
* pieState.c
*
* renderer setup and state control routines for 3D rendering
*
*/
/***************************************************************************/
#include "lib/framework/frame.h"
#include <SDL.h>
#include <SDL_opengl.h>
#include "lib/ivis_common/piestate.h"
#include "lib/ivis_common/piedef.h"
#include "lib/ivis_common/tex.h"
#include "lib/ivis_common/piepalette.h"
/***************************************************************************/
/*
* Global Variables
*/
/***************************************************************************/
extern RENDER_STATE rendStates;
/***************************************************************************/
/*
* Source
*/
/***************************************************************************/
void pie_SetDepthBufferStatus(DEPTH_MODE depthMode) {
switch(depthMode) {
case DEPTH_CMP_LEQ_WRT_ON:
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
glDepthMask(GL_TRUE);
break;
case DEPTH_CMP_ALWAYS_WRT_ON:
glDisable(GL_DEPTH_TEST);
glDepthMask(GL_TRUE);
break;
case DEPTH_CMP_LEQ_WRT_OFF:
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
glDepthMask(GL_FALSE);
break;
case DEPTH_CMP_ALWAYS_WRT_OFF:
glDisable(GL_DEPTH_TEST);
glDepthMask(GL_FALSE);
break;
}
}
/// Set the depth (z) offset
/// Negative values are closer to the screen
void pie_SetDepthOffset(float offset)
{
if(offset == 0.0f)
{
glDisable (GL_POLYGON_OFFSET_FILL);
}
else
{
glPolygonOffset(offset, offset);
glEnable (GL_POLYGON_OFFSET_FILL);
}
}
/// Set the OpenGL fog start and end
void pie_UpdateFogDistance(float begin, float end)
{
glFogf(GL_FOG_START, begin);
glFogf(GL_FOG_END, end);
}
//***************************************************************************
//
// pie_SetFogStatus(BOOL val)
//
// Toggle fog on and off for rendering objects inside or outside the 3D world
//
//***************************************************************************
void pie_SetFogStatus(BOOL val)
{
float fog_colour[4];
if (rendStates.fogEnabled)
{
//fog enabled so toggle if required
if (rendStates.fog != val)
{
rendStates.fog = val;
if (rendStates.fog) {
PIELIGHT fog = pie_GetFogColour();
fog_colour[0] = fog.byte.r/255.0f;
fog_colour[1] = fog.byte.g/255.0f;
fog_colour[2] = fog.byte.b/255.0f;
fog_colour[3] = fog.byte.a/255.0f;
glFogi(GL_FOG_MODE, GL_LINEAR);
glFogfv(GL_FOG_COLOR, fog_colour);
glFogf(GL_FOG_DENSITY, 0.35f);
glHint(GL_FOG_HINT, GL_DONT_CARE);
glEnable(GL_FOG);
} else {
glDisable(GL_FOG);
}
}
}
else
{
//fog disabled so turn it off if not off already
if (rendStates.fog != FALSE)
{
rendStates.fog = FALSE;
}
}
}
/***************************************************************************/
void pie_SetTexturePage(SDWORD num)
{
if (num != rendStates.texPage) {
rendStates.texPage = num;
if (num < 0) {
glDisable(GL_TEXTURE_2D);
} else {
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, _TEX_PAGE[num].id);
}
}
}
/***************************************************************************/
void pie_SetColourKeyedBlack(BOOL keyingOn)
{
if (keyingOn != rendStates.keyingOn)
{
rendStates.keyingOn = keyingOn;
pieStateCount++;
if (keyingOn == TRUE) {
glEnable(GL_ALPHA_TEST);
glAlphaFunc(GL_GREATER, 0.1f);
} else {
glDisable(GL_ALPHA_TEST);
}
}
}
/***************************************************************************/
void pie_SetColourCombine(COLOUR_MODE colCombMode)
{
if (colCombMode != rendStates.colourCombine) {
rendStates.colourCombine = colCombMode;
pieStateCount++;
switch (colCombMode) {
case COLOUR_FLAT_CONSTANT:
case COLOUR_FLAT_ITERATED:
pie_SetTexturePage(-1);
break;
case COLOUR_TEX_CONSTANT:
case COLOUR_TEX_ITERATED:
default:
break;
}
}
}
/***************************************************************************/
void pie_SetTranslucencyMode(TRANSLUCENCY_MODE transMode)
{
if (transMode != rendStates.transMode) {
rendStates.transMode = transMode;
switch (transMode) {
case TRANS_ALPHA:
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
break;
case TRANS_ADDITIVE:
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE);
break;
case TRANS_FILTER:
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_SRC_COLOR);
break;
default:
rendStates.transMode = TRANS_DECAL;
glDisable(GL_BLEND);
break;
}
}
}
/***************************************************************************/
void pie_SetGammaValue(float val)
{
debug(LOG_VIDEO, "%s(%f)", __FUNCTION__, val);
SDL_SetGamma(val, val, val);
}