+
+ /* Setup vertex texcoords. This is a little tricky for cube maps. */
+ if (tex_target == PIPE_TEXTURE_CUBE) {
+ static const float st[4][2] = {
+ {0.0f, 0.0f}, {1.0f, 0.0f}, {1.0f, 1.0f}, {0.0f, 1.0f}
+ };
+ float rx, ry, rz;
+ uint i;
+
+ /* loop over quad verts */
+ for (i = 0; i < 4; i++) {
+ /* Compute sc = +/-scale and tc = +/-scale.
+ * Not +/-1 to avoid cube face selection ambiguity near the edges,
+ * though that can still sometimes happen with this scale factor...
+ */
+ const float scale = 0.9999f;
+ const float sc = (2.0f * st[i][0] - 1.0f) * scale;
+ const float tc = (2.0f * st[i][1] - 1.0f) * scale;
+
+ switch (face) {
+ case PIPE_TEX_FACE_POS_X:
+ rx = 1.0f;
+ ry = -tc;
+ rz = -sc;
+ break;
+ case PIPE_TEX_FACE_NEG_X:
+ rx = -1.0f;
+ ry = -tc;
+ rz = sc;
+ break;
+ case PIPE_TEX_FACE_POS_Y:
+ rx = sc;
+ ry = 1.0f;
+ rz = tc;
+ break;
+ case PIPE_TEX_FACE_NEG_Y:
+ rx = sc;
+ ry = -1.0f;
+ rz = -tc;
+ break;
+ case PIPE_TEX_FACE_POS_Z:
+ rx = sc;
+ ry = -tc;
+ rz = 1.0f;
+ break;
+ case PIPE_TEX_FACE_NEG_Z:
+ rx = -sc;
+ ry = -tc;
+ rz = -1.0f;
+ break;
+ default:
+ assert(0);
+ }
+
+ ctx->vertices[i][1][0] = rx; /*s*/
+ ctx->vertices[i][1][1] = ry; /*t*/
+ ctx->vertices[i][1][2] = rz; /*r*/
+ }
+ }
+ else {
+ /* 1D/2D */
+ ctx->vertices[0][1][0] = 0.0f; /*s*/
+ ctx->vertices[0][1][1] = 0.0f; /*t*/
+ ctx->vertices[0][1][2] = 0.0f; /*r*/
+
+ ctx->vertices[1][1][0] = 1.0f;
+ ctx->vertices[1][1][1] = 0.0f;
+ ctx->vertices[1][1][2] = 0.0f;
+
+ ctx->vertices[2][1][0] = 1.0f;
+ ctx->vertices[2][1][1] = 1.0f;
+ ctx->vertices[2][1][2] = 0.0f;
+
+ ctx->vertices[3][1][0] = 0.0f;
+ ctx->vertices[3][1][1] = 1.0f;
+ ctx->vertices[3][1][2] = 0.0f;
+ }