/* Only 3 elements are used, the 4th is ignored */
void x86_opengl_vector_unit(GLfloat *dst, GLfloat *p1, GLfloat *p2)
{
if (p1[3] == 0 && p2[3] !=0)
ACC_SCALE_SCALAR_3V(dst, -1.0f, p1);
else if (p1[3] != 0 && p2[3] ==0)
COPY_3V(dst, p2);
else if (p1[3] == 0 && p2[3] == 0)
SUB_3V(dst, p2, p1);
else
SUB_3V(dst, p2, p1);
NORMALIZE_3FV(dst);
}
/**
* Compute lighting for the raster position. RGB modes computed.
* \param ctx the context
* \param vertex vertex location
* \param normal normal vector
* \param Rcolor returned color
* \param Rspec returned specular color (if separate specular enabled)
*/
static void
shade_rastpos(struct gl_context *ctx,
const GLfloat vertex[4],
const GLfloat normal[3],
GLfloat Rcolor[4],
GLfloat Rspec[4])
{
/*const*/ GLfloat (*base)[3] = ctx->Light._BaseColor;
GLbitfield mask;
GLfloat diffuseColor[4], specularColor[4]; /* for RGB mode only */
COPY_3V(diffuseColor, base[0]);
diffuseColor[3] = CLAMP(
ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3], 0.0F, 1.0F );
ASSIGN_4V(specularColor, 0.0, 0.0, 0.0, 1.0);
mask = ctx->Light._EnabledLights;
while (mask) {
const int i = u_bit_scan(&mask);
struct gl_light *light = &ctx->Light.Light[i];
GLfloat attenuation = 1.0;
GLfloat VP[3]; /* vector from vertex to light pos */
GLfloat n_dot_VP;
GLfloat diffuseContrib[3], specularContrib[3];
if (!(light->_Flags & LIGHT_POSITIONAL)) {
/* light at infinity */
COPY_3V(VP, light->_VP_inf_norm);
attenuation = light->_VP_inf_spot_attenuation;
}
else {
/* local/positional light */
GLfloat d;
/* VP = vector from vertex pos to light[i].pos */
SUB_3V(VP, light->_Position, vertex);
/* d = length(VP) */
d = (GLfloat) LEN_3FV( VP );
if (d > 1.0e-6F) {
/* normalize VP */
GLfloat invd = 1.0F / d;
SELF_SCALE_SCALAR_3V(VP, invd);
}
/* atti */
attenuation = 1.0F / (light->ConstantAttenuation + d *
(light->LinearAttenuation + d *
light->QuadraticAttenuation));
if (light->_Flags & LIGHT_SPOT) {
GLfloat PV_dot_dir = - DOT3(VP, light->_NormSpotDirection);
if (PV_dot_dir<light->_CosCutoff) {
continue;
}
else {
GLfloat spot = powf(PV_dot_dir, light->SpotExponent);
attenuation *= spot;
}
}
}
if (attenuation < 1e-3F)
continue;
n_dot_VP = DOT3( normal, VP );
if (n_dot_VP < 0.0F) {
ACC_SCALE_SCALAR_3V(diffuseColor, attenuation, light->_MatAmbient[0]);
continue;
}
/* Ambient + diffuse */
COPY_3V(diffuseContrib, light->_MatAmbient[0]);
ACC_SCALE_SCALAR_3V(diffuseContrib, n_dot_VP, light->_MatDiffuse[0]);
/* Specular */
{
const GLfloat *h;
GLfloat n_dot_h;
ASSIGN_3V(specularContrib, 0.0, 0.0, 0.0);
if (ctx->Light.Model.LocalViewer) {
GLfloat v[3];
COPY_3V(v, vertex);
NORMALIZE_3FV(v);
SUB_3V(VP, VP, v);
NORMALIZE_3FV(VP);
h = VP;
}
else if (light->_Flags & LIGHT_POSITIONAL) {
ACC_3V(VP, ctx->_EyeZDir);
NORMALIZE_3FV(VP);
h = VP;
}
else {
h = light->_h_inf_norm;
}
n_dot_h = DOT3(normal, h);
if (n_dot_h > 0.0F) {
GLfloat shine;
GLfloat spec_coef;
shine = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_SHININESS][0];
spec_coef = powf(n_dot_h, shine);
if (spec_coef > 1.0e-10F) {
if (ctx->Light.Model.ColorControl==GL_SEPARATE_SPECULAR_COLOR) {
ACC_SCALE_SCALAR_3V( specularContrib, spec_coef,
light->_MatSpecular[0]);
}
else {
ACC_SCALE_SCALAR_3V( diffuseContrib, spec_coef,
light->_MatSpecular[0]);
}
}
}
}
ACC_SCALE_SCALAR_3V( diffuseColor, attenuation, diffuseContrib );
ACC_SCALE_SCALAR_3V( specularColor, attenuation, specularContrib );
}
Rcolor[0] = CLAMP(diffuseColor[0], 0.0F, 1.0F);
Rcolor[1] = CLAMP(diffuseColor[1], 0.0F, 1.0F);
Rcolor[2] = CLAMP(diffuseColor[2], 0.0F, 1.0F);
Rcolor[3] = CLAMP(diffuseColor[3], 0.0F, 1.0F);
Rspec[0] = CLAMP(specularColor[0], 0.0F, 1.0F);
Rspec[1] = CLAMP(specularColor[1], 0.0F, 1.0F);
Rspec[2] = CLAMP(specularColor[2], 0.0F, 1.0F);
Rspec[3] = CLAMP(specularColor[3], 0.0F, 1.0F);
}
/**
* Determine type and flags from scratch.
*
* \param mat matrix.
*
* This is expensive enough to only want to do it once.
*/
static void analyse_from_scratch( GLmatrix *mat )
{
const GLfloat *m = mat->m;
GLuint mask = 0;
GLuint i;
for (i = 0 ; i < 16 ; i++) {
if (m[i] == 0.0) mask |= (1<<i);
}
if (m[0] == 1.0F) mask |= (1<<16);
if (m[5] == 1.0F) mask |= (1<<21);
if (m[10] == 1.0F) mask |= (1<<26);
if (m[15] == 1.0F) mask |= (1<<31);
mat->flags &= ~MAT_FLAGS_GEOMETRY;
/* Check for translation - no-one really cares
*/
if ((mask & MASK_NO_TRX) != MASK_NO_TRX)
mat->flags |= MAT_FLAG_TRANSLATION;
/* Do the real work
*/
if (mask == (GLuint) MASK_IDENTITY) {
mat->type = MATRIX_IDENTITY;
}
else if ((mask & MASK_2D_NO_ROT) == (GLuint) MASK_2D_NO_ROT) {
mat->type = MATRIX_2D_NO_ROT;
if ((mask & MASK_NO_2D_SCALE) != MASK_NO_2D_SCALE)
mat->flags |= MAT_FLAG_GENERAL_SCALE;
}
else if ((mask & MASK_2D) == (GLuint) MASK_2D) {
GLfloat mm = DOT2(m, m);
GLfloat m4m4 = DOT2(m+4,m+4);
GLfloat mm4 = DOT2(m,m+4);
mat->type = MATRIX_2D;
/* Check for scale */
if (SQ(mm-1) > SQ(1e-6) ||
SQ(m4m4-1) > SQ(1e-6))
mat->flags |= MAT_FLAG_GENERAL_SCALE;
/* Check for rotation */
if (SQ(mm4) > SQ(1e-6))
mat->flags |= MAT_FLAG_GENERAL_3D;
else
mat->flags |= MAT_FLAG_ROTATION;
}
else if ((mask & MASK_3D_NO_ROT) == (GLuint) MASK_3D_NO_ROT) {
mat->type = MATRIX_3D_NO_ROT;
/* Check for scale */
if (SQ(m[0]-m[5]) < SQ(1e-6) &&
SQ(m[0]-m[10]) < SQ(1e-6)) {
if (SQ(m[0]-1.0) > SQ(1e-6)) {
mat->flags |= MAT_FLAG_UNIFORM_SCALE;
}
}
else {
mat->flags |= MAT_FLAG_GENERAL_SCALE;
}
}
else if ((mask & MASK_3D) == (GLuint) MASK_3D) {
GLfloat c1 = DOT3(m,m);
GLfloat c2 = DOT3(m+4,m+4);
GLfloat c3 = DOT3(m+8,m+8);
GLfloat d1 = DOT3(m, m+4);
GLfloat cp[3];
mat->type = MATRIX_3D;
/* Check for scale */
if (SQ(c1-c2) < SQ(1e-6) && SQ(c1-c3) < SQ(1e-6)) {
if (SQ(c1-1.0) > SQ(1e-6))
mat->flags |= MAT_FLAG_UNIFORM_SCALE;
/* else no scale at all */
}
else {
mat->flags |= MAT_FLAG_GENERAL_SCALE;
}
/* Check for rotation */
if (SQ(d1) < SQ(1e-6)) {
CROSS3( cp, m, m+4 );
SUB_3V( cp, cp, (m+8) );
if (LEN_SQUARED_3FV(cp) < SQ(1e-6))
mat->flags |= MAT_FLAG_ROTATION;
else
mat->flags |= MAT_FLAG_GENERAL_3D;
}
else {
mat->flags |= MAT_FLAG_GENERAL_3D; /* shear, etc */
}
}
else if ((mask & MASK_PERSPECTIVE) == MASK_PERSPECTIVE && m[11]==-1.0F) {
mat->type = MATRIX_PERSPECTIVE;
mat->flags |= MAT_FLAG_GENERAL;
}
else {
mat->type = MATRIX_GENERAL;
mat->flags |= MAT_FLAG_GENERAL;
}
}
