shader: Fix texelFetch to emulated 1D textures on GLES

GLES doesn't support 1D textures, so they are emulated by using 2D
textures and the access has to be fixed by adding the y lookup coordinate.

v2: simplify the code flow (Gurchetan)

Signed-off-by: Gert Wollny <gert.wollny@collabora.com>
Reviewed-by: <Gurchetan Singh gurchetansingh@chromium.org>

src/vrend_shader.c

@@ -2248,7 +2248,16 @@ static void translate_tex(struct dump_ctx *ctx,
       }
    }
    if (inst->Instruction.Opcode == TGSI_OPCODE_TXF) {
-      emit_buff(ctx, "%s = %s(%s(texelFetch%s(%s, %s(%s%s)%s%s)%s));\n", dsts[0], get_string(dinfo->dstconv), get_string(dtypeprefix), tex_ext, srcs[sampler_index], get_string(txfi), srcs[0], get_wm_string(twm), bias, offbuf, dinfo->dst_override_no_wm[0] ? "" : writemask);
+      if (ctx->cfg->use_gles && (inst->Texture.Texture == TGSI_TEXTURE_1D ||
+                                 inst->Texture.Texture == TGSI_TEXTURE_1D_ARRAY)) {
+         const char *vtype = inst->Texture.Texture == TGSI_TEXTURE_1D ? "vec2" : "vec3";
+         emit_buff(ctx, "%s = %s(%s(texelFetch%s(%s, %s(%s(%s%s), 0)%s%s)%s));\n",
+                   dsts[0], get_string(dinfo->dstconv), get_string(dtypeprefix), tex_ext, srcs[sampler_index],
+                   vtype, get_string(txfi), srcs[0], get_wm_string(twm), bias, offbuf, dinfo->dst_override_no_wm[0] ? "" : writemask);
+      } else {
+         emit_buff(ctx, "%s = %s(%s(texelFetch%s(%s, %s(%s%s)%s%s)%s));\n", dsts[0], get_string(dinfo->dstconv), get_string(dtypeprefix),
+               tex_ext, srcs[sampler_index], get_string(txfi), srcs[0], get_wm_string(twm), bias, offbuf, dinfo->dst_override_no_wm[0] ? "" : writemask);
+      }
    } else if (ctx->cfg->glsl_version < 140 && (ctx->shader_req_bits & SHADER_REQ_SAMPLER_RECT)) {
       /* rect is special in GLSL 1.30 */
       if (inst->Texture.Texture == TGSI_TEXTURE_RECT)