cedric pushed a commit to branch master.
http://git.enlightenment.org/core/efl.git/commit/?id=d602597ac1eec0cf357e0f47de85b6f7290b7da0
commit d602597ac1eec0cf357e0f47de85b6f7290b7da0
Author: Dmytro Dadyka <d.dad...@samsung.com>
Date: Thu Feb 26 20:42:36 2015 +0100
evas: Evas_3D - add terrain mesh.
Reviewers: Hermet, Oleksander, cedric
Subscribers: cedric
Differential Revision: https://phab.enlightenment.org/D2042
Signed-off-by: Cedric BAIL <ced...@osg.samsung.com>
---
src/examples/evas/evas-3d-primitives.c | 85 ++++++++++++++++++++++++++++++++++
src/examples/evas/evas-3d-primitives.h | 4 ++
2 files changed, 89 insertions(+)
diff --git a/src/examples/evas/evas-3d-primitives.c
b/src/examples/evas/evas-3d-primitives.c
index 4fefb5a..f98ecb7 100644
--- a/src/examples/evas/evas-3d-primitives.c
+++ b/src/examples/evas/evas-3d-primitives.c
@@ -162,6 +162,80 @@ vec3 _get_func_normal(Surface *func, float x, float y)
return normal;
}
+static float
+_random(int x, int y)
+{
+ int k = x + y * 57;
+ k = (k << 13) ^ k;
+ return (1.0f - ((k * (k * k * 15731 + 789221) + 1376312589) & 0x7fffffff) /
+ 1073741824.0f);
+}
+
+static float
+_smooth(float x, float y)
+{
+ float res;
+ res = (_random(x - 1, y - 1) + _random(x + 1, y - 1) +
+ _random(x - 1, y + 1) + _random(x + 1, y + 1) ) / 16;
+ res += (_random(x - 1, y) + _random(x + 1, y) +
+ _random(x, y - 1) + _random(x, y + 1)) / 8;
+ res += _random(x, y) / 4;
+ return res;
+}
+
+static float
+_interpolate(float a, float b, float x)
+{
+ float ft = x * M_PI;
+ float f = (1 - cosf(ft)) * 0.5;
+ return a * (1 - f) + b * f;
+}
+
+static float _noise(float x, float y)
+{
+ float ix = (int)(x);
+ float fx = x - ix;
+ float iy = (int)(y);
+ float fy = y - iy;
+
+ float v1 = _smooth(ix, iy);
+ float v2 = _smooth(ix + 1, iy);
+ float v3 = _smooth(ix, iy + 1);
+ float v4 = _smooth(ix + 1, iy + 1);
+
+ float i1 = _interpolate(v1, v2, fx);
+ float i2 = _interpolate(v3, v4, fx);
+
+ return _interpolate(i1, i2, fy);
+}
+
+static vec3
+_perlin_terrain(float x,float y)
+{
+ vec3 out;
+ float persistence = 0.5f;
+ float frequency = 5;
+ float amplitude = 1;
+ int i = 0;
+ int octaves = 5;
+
+ out.x = x;
+ x += 0.5;
+ out.y = y;
+ y += 0.5;
+ out.z = 0;
+
+ for(i = 0;i < octaves; i++)
+ {
+ out.z += _noise(x * frequency, y * frequency) * amplitude;
+
+ amplitude *= persistence;
+ frequency *= 2;
+ }
+
+ return out;
+}
+
void
_generate_grid_indices(unsigned short *indices, int count)
{
@@ -265,6 +339,11 @@ evas_3d_add_func_surface_frame(Eo *mesh, int frame,
Surface func, int p, vec2 te
vertices[i + j * vccount] = func(v, u);
normals[i + j * vccount] = _get_func_normal(func, v, u);
+ // TODO Add tangent calculation
+ tangents[i + j * vccount].x = 0;
+ tangents[i + j * vccount].y = 0;
+ tangents[i + j * vccount].z = 0;
+
tex_coord[i + j * vccount].x = i / (float)(vccount - 1) *
tex_scale.x;
tex_coord[i + j *vccount].y = tex_scale.y - j / (float)(vccount -
1) * tex_scale.y;
}
@@ -275,6 +354,12 @@ evas_3d_add_func_surface_frame(Eo *mesh, int frame,
Surface func, int p, vec2 te
}
void
+evas_3d_add_terrain_frame(Eo *mesh, int frame, int p, vec2 tex_scale)
+{
+ evas_3d_add_func_surface_frame(mesh, frame, _perlin_terrain, p, tex_scale);
+}
+
+void
evas_3d_add_torus_frame(Eo *mesh, int frame, float rratio, int p, vec2
tex_scale)
{
int vcount, icount, vccount, i, j;
diff --git a/src/examples/evas/evas-3d-primitives.h
b/src/examples/evas/evas-3d-primitives.h
index 3281f5d..c08ae65 100644
--- a/src/examples/evas/evas-3d-primitives.h
+++ b/src/examples/evas/evas-3d-primitives.h
@@ -52,4 +52,8 @@ evas_3d_add_square_frame(Eo *mesh, int frame);
void
evas_3d_add_cube_frame(Eo *mesh, int frame);
+/* Set frame as terrain generated by perlin noise algorithm*/
+void
+evas_3d_add_terrain_frame(Eo *mesh, int frame, int precision, vec2 tex_scale);
+
#endif // EVAS_3D_PRIMITIVES_H
--
