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authorJuha-Pekka Heikkila <[email protected]>2014-04-02 16:13:57 +0300
committerTapani Pälli <[email protected]>2014-04-02 19:54:37 +0300
commit68a45b130e12d5a1d6c7dca20a930b9433ec1992 (patch)
tree46bf02818bbb89ec6fc7c7dcaa8f0f11bb67ac8d
parent1056c50d574eebaf5a1769f52d95b022aaf27c80 (diff)
mesa: Prevent negative indexing on noise2, noise3 and noise4
% operator could return negative value which would cause indexing before perm table. Change %256 to &0xff Signed-off-by: Juha-Pekka Heikkila <[email protected]> Reviewed-by: Matt Turner <[email protected]>
-rw-r--r--src/mesa/program/prog_noise.c36
1 files changed, 18 insertions, 18 deletions
diff --git a/src/mesa/program/prog_noise.c b/src/mesa/program/prog_noise.c
index c258c5e2e06..ac920c23f34 100644
--- a/src/mesa/program/prog_noise.c
+++ b/src/mesa/program/prog_noise.c
@@ -257,12 +257,12 @@ _mesa_noise2(GLfloat x, GLfloat y)
float y0 = y - Y0;
float x1, y1, x2, y2;
- int ii, jj;
+ unsigned int ii, jj;
float t0, t1, t2;
/* For the 2D case, the simplex shape is an equilateral triangle. */
/* Determine which simplex we are in. */
- int i1, j1; /* Offsets for second (middle) corner of simplex in (i,j) coords */
+ unsigned int i1, j1; /* Offsets for second (middle) corner of simplex in (i,j) coords */
if (x0 > y0) {
i1 = 1;
j1 = 0;
@@ -282,8 +282,8 @@ _mesa_noise2(GLfloat x, GLfloat y)
y2 = y0 - 1.0f + 2.0f * G2;
/* Wrap the integer indices at 256, to avoid indexing perm[] out of bounds */
- ii = i % 256;
- jj = j % 256;
+ ii = i & 0xff;
+ jj = j & 0xff;
/* Calculate the contribution from the three corners */
t0 = 0.5f - x0 * x0 - y0 * y0;
@@ -344,13 +344,13 @@ _mesa_noise3(GLfloat x, GLfloat y, GLfloat z)
float z0 = z - Z0;
float x1, y1, z1, x2, y2, z2, x3, y3, z3;
- int ii, jj, kk;
+ unsigned int ii, jj, kk;
float t0, t1, t2, t3;
/* For the 3D case, the simplex shape is a slightly irregular tetrahedron. */
/* Determine which simplex we are in. */
- int i1, j1, k1; /* Offsets for second corner of simplex in (i,j,k) coords */
- int i2, j2, k2; /* Offsets for third corner of simplex in (i,j,k) coords */
+ unsigned int i1, j1, k1; /* Offsets for second corner of simplex in (i,j,k) coords */
+ unsigned int i2, j2, k2; /* Offsets for third corner of simplex in (i,j,k) coords */
/* This code would benefit from a backport from the GLSL version! */
if (x0 >= y0) {
@@ -423,9 +423,9 @@ _mesa_noise3(GLfloat x, GLfloat y, GLfloat z)
z3 = z0 - 1.0f + 3.0f * G3;
/* Wrap the integer indices at 256 to avoid indexing perm[] out of bounds */
- ii = i % 256;
- jj = j % 256;
- kk = k % 256;
+ ii = i & 0xff;
+ jj = j & 0xff;
+ kk = k & 0xff;
/* Calculate the contribution from the four corners */
t0 = 0.6f - x0 * x0 - y0 * y0 - z0 * z0;
@@ -522,12 +522,12 @@ _mesa_noise4(GLfloat x, GLfloat y, GLfloat z, GLfloat w)
int c6 = (z0 > w0) ? 1 : 0;
int c = c1 + c2 + c3 + c4 + c5 + c6;
- int i1, j1, k1, l1; /* The integer offsets for the second simplex corner */
- int i2, j2, k2, l2; /* The integer offsets for the third simplex corner */
- int i3, j3, k3, l3; /* The integer offsets for the fourth simplex corner */
+ unsigned int i1, j1, k1, l1; /* The integer offsets for the second simplex corner */
+ unsigned int i2, j2, k2, l2; /* The integer offsets for the third simplex corner */
+ unsigned int i3, j3, k3, l3; /* The integer offsets for the fourth simplex corner */
float x1, y1, z1, w1, x2, y2, z2, w2, x3, y3, z3, w3, x4, y4, z4, w4;
- int ii, jj, kk, ll;
+ unsigned int ii, jj, kk, ll;
float t0, t1, t2, t3, t4;
/*
@@ -573,10 +573,10 @@ _mesa_noise4(GLfloat x, GLfloat y, GLfloat z, GLfloat w)
w4 = w0 - 1.0f + 4.0f * G4;
/* Wrap the integer indices at 256, to avoid indexing perm[] out of bounds */
- ii = i % 256;
- jj = j % 256;
- kk = k % 256;
- ll = l % 256;
+ ii = i & 0xff;
+ jj = j & 0xff;
+ kk = k & 0xff;
+ ll = l & 0xff;
/* Calculate the contribution from the five corners */
t0 = 0.6f - x0 * x0 - y0 * y0 - z0 * z0 - w0 * w0;