Framebuffer::Framebuffer(int width, int height)
: width(width), height(height), id(allocFramebuffer()), texId(allocTexture(width, height)) {
SDL::glBindFramebuffer(GL_FRAMEBUFFER, id);
SDL::glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texId, 0);
SDL::GLenum drawTargets[1] = {GL_COLOR_ATTACHMENT0};
SDL::glDrawBuffers(1, drawTargets);
auto ret = SDL::glCheckFramebufferStatus(GL_FRAMEBUFFER);
CHECK(ret == GL_FRAMEBUFFER_COMPLETE);
unbind();
}
static int
fboPrologue (CompScreen *s,
int tIndex)
{
WATER_SCREEN (s);
if (!ws->fbo)
return 0;
if (!ws->texture[tIndex])
allocTexture (s, tIndex);
(*s->bindFramebuffer) (GL_FRAMEBUFFER_EXT, ws->fbo);
(*s->framebufferTexture2D) (GL_FRAMEBUFFER_EXT,
GL_COLOR_ATTACHMENT0_EXT,
ws->target, ws->texture[tIndex],
0);
glDrawBuffer (GL_COLOR_ATTACHMENT0_EXT);
glReadBuffer (GL_COLOR_ATTACHMENT0_EXT);
/* check status the first time */
if (!ws->fboStatus)
{
ws->fboStatus = (*s->checkFramebufferStatus) (GL_FRAMEBUFFER_EXT);
if (ws->fboStatus != GL_FRAMEBUFFER_COMPLETE_EXT)
{
compLogMessage ("water", CompLogLevelError,
"framebuffer incomplete");
(*s->bindFramebuffer) (GL_FRAMEBUFFER_EXT, 0);
(*s->deleteFramebuffers) (1, &ws->fbo);
glDrawBuffer (GL_BACK);
glReadBuffer (GL_BACK);
ws->fbo = 0;
return 0;
}
}
glViewport (0, 0, ws->width, ws->height);
glMatrixMode (GL_PROJECTION);
glPushMatrix ();
glLoadIdentity ();
glOrtho (0.0, 1.0, 0.0, 1.0, -1.0, 1.0);
glMatrixMode (GL_MODELVIEW);
glPushMatrix ();
glLoadIdentity ();
return 1;
}
static void softwareUpdate(CompScreen * s, float dt, float fade)
{
float *dTmp;
int i, j;
float v0, v1, inv;
float accel, value;
unsigned char *t0, *t;
int dWidth, dHeight;
float *d01, *d10, *d11, *d12;
WATER_SCREEN(s);
if (!ws->texture[TINDEX(ws, 0)])
allocTexture(s, TINDEX(ws, 0));
dt *= K * 2.0f;
fade *= 0.99f;
dWidth = ws->width + 2;
dHeight = ws->height + 2;
#define D(d, j) (*((d) + (j)))
d01 = ws->d0 + dWidth;
d10 = ws->d1;
d11 = d10 + dWidth;
d12 = d11 + dWidth;
for (i = 1; i < dHeight - 1; i++) {
for (j = 1; j < dWidth - 1; j++) {
accel = dt * (D(d10, j) +
D(d12, j) +
D(d11, j - 1) +
D(d11, j + 1) - 4.0f * D(d11, j));
value = (2.0f * D(d11, j) - D(d01, j) + accel) * fade;
CLAMP(value, 0.0f, 1.0f);
D(d01, j) = value;
}
d01 += dWidth;
d10 += dWidth;
d11 += dWidth;
d12 += dWidth;
}
/* update border */
memcpy(ws->d0, ws->d0 + dWidth, dWidth * sizeof(GLfloat));
memcpy(ws->d0 + dWidth * (dHeight - 1),
ws->d0 + dWidth * (dHeight - 2), dWidth * sizeof(GLfloat));
d01 = ws->d0 + dWidth;
for (i = 1; i < dHeight - 1; i++) {
D(d01, 0) = D(d01, 1);
D(d01, dWidth - 1) = D(d01, dWidth - 2);
d01 += dWidth;
}
d10 = ws->d1;
d11 = d10 + dWidth;
d12 = d11 + dWidth;
t0 = ws->t0;
/* update texture */
for (i = 0; i < ws->height; i++) {
for (j = 0; j < ws->width; j++) {
v0 = (D(d12, j) - D(d10, j)) * 1.5f;
v1 = (D(d11, j - 1) - D(d11, j + 1)) * 1.5f;
/* 0.5 for scale */
inv = 0.5f / sqrtf(v0 * v0 + v1 * v1 + 1.0f);
/* add scale and bias to normal */
v0 = v0 * inv + 0.5f;
v1 = v1 * inv + 0.5f;
/* store normal map in RGB components */
t = t0 + (j * 4);
t[0] = (unsigned char)((inv + 0.5f) * 255.0f);
t[1] = (unsigned char)(v1 * 255.0f);
t[2] = (unsigned char)(v0 * 255.0f);
/* store height in A component */
t[3] = (unsigned char)(D(d11, j) * 255.0f);
}
d10 += dWidth;
d11 += dWidth;
d12 += dWidth;
t0 += ws->width * 4;
}
#undef D
/* swap height maps */
dTmp = ws->d0;
ws->d0 = ws->d1;
ws->d1 = dTmp;
if (ws->texture[TINDEX(ws, 0)]) {
glBindTexture(ws->target, ws->texture[TINDEX(ws, 0)]);
glTexImage2D(ws->target,
0, GL_RGBA, ws->width, ws->height, 0, GL_BGRA,
#if IMAGE_BYTE_ORDER == MSBFirst
GL_UNSIGNED_INT_8_8_8_8_REV,
#else
GL_UNSIGNED_BYTE,
#endif
ws->t0);
}
}
static int fboUpdate(CompScreen * s, float dt, float fade)
{
WATER_SCREEN(s);
if (!fboPrologue(s, TINDEX(ws, 1)))
return 0;
if (!ws->texture[TINDEX(ws, 2)])
allocTexture(s, TINDEX(ws, 2));
if (!ws->texture[TINDEX(ws, 0)])
allocTexture(s, TINDEX(ws, 0));
glEnable(ws->target);
(*s->activeTexture) (GL_TEXTURE0_ARB);
glBindTexture(ws->target, ws->texture[TINDEX(ws, 2)]);
glTexParameteri(ws->target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(ws->target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
(*s->activeTexture) (GL_TEXTURE1_ARB);
glBindTexture(ws->target, ws->texture[TINDEX(ws, 0)]);
glTexParameteri(ws->target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(ws->target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glEnable(GL_FRAGMENT_PROGRAM_ARB);
(*s->bindProgram) (GL_FRAGMENT_PROGRAM_ARB, ws->program);
(*s->programLocalParameter4f) (GL_FRAGMENT_PROGRAM_ARB, 0,
dt * K, fade, 1.0f, 1.0f);
glBegin(GL_QUADS);
glTexCoord2f(0.0f, 0.0f);
glVertex2f(0.0f, 0.0f);
glTexCoord2f(ws->tx, 0.0f);
glVertex2f(1.0f, 0.0f);
glTexCoord2f(ws->tx, ws->ty);
glVertex2f(1.0f, 1.0f);
glTexCoord2f(0.0f, ws->ty);
glVertex2f(0.0f, 1.0f);
glEnd();
glDisable(GL_FRAGMENT_PROGRAM_ARB);
glTexParameteri(ws->target, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(ws->target, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glBindTexture(ws->target, 0);
(*s->activeTexture) (GL_TEXTURE0_ARB);
glTexParameteri(ws->target, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(ws->target, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glBindTexture(ws->target, 0);
glDisable(ws->target);
fboEpilogue(s);
/* increment texture index */
ws->tIndex = TINDEX(ws, 1);
return 1;
}
