GLSL parser: Rework precision qualifier patching

Since precision qualifiers can be used in multiple places (or can be
provided using preprocessor), they are now handled by adding following
statements to shader header (if needed):
    #define highp
    #define mediump
    #define lowp

Parser has been adjusted to pass forward precision qualifiers instead of
patching them.

Change-Id: I002fb62b7ddee0d00a81a60f6b082694c2f9653e

diff --git a/GLESv2/yagl_glsl_lexer.l b/GLESv2/yagl_glsl_lexer.l
index 026aba04e018d7adcdd330eeafff8b15596070ef..c0515726834c3c9076ec279623724490b3236bc0 100644 (file)
--- a/GLESv2/yagl_glsl_lexer.l
+++ b/GLESv2/yagl_glsl_lexer.l
@@ -252,12 +252,6 @@ PP_FUNCTION {STRING}{WS}*\([^\n]+
     return TOK_GLFRAGCOLOR;
 }
 
-{PRECISION_QUAL} {
-    struct yagl_glsl_state *state = yagl_glsl_lexer_get_extra(yyscanner);
-    yagl_glsl_state_new_str_token(state, yylval, yytext);
-    return TOK_PRECISION_QUAL;
-}
-
 "precision" {
     struct yagl_glsl_state *state = yagl_glsl_lexer_get_extra(yyscanner);
     BEGIN(PRECISION);
@@ -574,12 +568,6 @@ PP_FUNCTION {STRING}{WS}*\([^\n]+
     return TOK_INTEGER;
 }
 
-<UNIFORM>{PRECISION_QUAL} {
-    struct yagl_glsl_state *state = yagl_glsl_lexer_get_extra(yyscanner);
-    yagl_glsl_state_new_str_token(state, yylval, yytext);
-    return TOK_PRECISION_QUAL;
-}
-
 <UNIFORM>{STRING} {
     struct yagl_glsl_state *state = yagl_glsl_lexer_get_extra(yyscanner);
     yagl_glsl_state_new_str_token(state, yylval, yytext);

diff --git a/GLESv2/yagl_glsl_parser.y b/GLESv2/yagl_glsl_parser.y
index 723694dd1dce938ff1c837dcee841f2312ea45ba..095bd71dc09d8190bde1bbceceec5ecb893ab8ba 100644 (file)
--- a/GLESv2/yagl_glsl_parser.y
+++ b/GLESv2/yagl_glsl_parser.y
@@ -673,16 +673,14 @@ expression
         yagl_glsl_state_append_output(state, $1.value);
     }
 }
-| TOK_UNIFORM TOK_PRECISION_QUAL TOK_STRING TOK_STRING TOK_ARR_PAREN_OPEN TOK_INTEGER TOK_ARR_PAREN_CLOSE TOK_EOI
+| TOK_UNIFORM TOK_STRING TOK_STRING TOK_STRING TOK_ARR_PAREN_OPEN TOK_INTEGER TOK_ARR_PAREN_CLOSE TOK_EOI
 {
     char s[100];
 
     yagl_glsl_state_flush_pending(state, $1.index);
     yagl_glsl_state_append_output(state, $1.value);
-
-    // precision qualifier should only be flushed here, GLSL non-ES does not support it
     yagl_glsl_state_flush_pending(state, $2.index);
-
+    yagl_glsl_state_append_output(state, $2.value);
     yagl_glsl_state_flush_pending(state, $3.index);
     yagl_glsl_state_append_output(state, $3.value);
     yagl_glsl_state_flush_pending(state, $4.index);
@@ -765,14 +763,12 @@ expression
         }
     }
 }
-| TOK_UNIFORM TOK_PRECISION_QUAL TOK_STRING TOK_STRING TOK_EOI
+| TOK_UNIFORM TOK_STRING TOK_STRING TOK_STRING TOK_EOI
 {
     yagl_glsl_state_flush_pending(state, $1.index);
     yagl_glsl_state_append_output(state, $1.value);
-
-    // precision qualifier should only be flushed here, GLSL non-ES does not support it
     yagl_glsl_state_flush_pending(state, $2.index);
-
+    yagl_glsl_state_append_output(state, $2.value);
     yagl_glsl_state_flush_pending(state, $3.index);
     yagl_glsl_state_append_output(state, $3.value);
     yagl_glsl_state_flush_pending(state, $4.index);

diff --git a/GLESv2/yagl_glsl_state.c b/GLESv2/yagl_glsl_state.c
index 2dcbb115ce535d09cc5a03f2c6558346af696ba4..2c538357db884cc2fd20b367c7733bf80792e849 100644 (file)
--- a/GLESv2/yagl_glsl_state.c
+++ b/GLESv2/yagl_glsl_state.c
@@ -106,13 +106,15 @@ static void yagl_glsl_state_flush_version(struct yagl_glsl_state *state)
 {
     int have_version = state->have_version;
     int have_extensions = state->have_extensions;
+    int have_precision = state->have_precision;
 
-    if (have_version && have_extensions) {
+    if (have_version && have_extensions && have_precision) {
         return;
     }
 
     state->have_version = 1;
     state->have_extensions = 1;
+    state->have_precision = 1;
 
     if (!have_version) {
         switch (state->patch_version) {
@@ -139,6 +141,14 @@ static void yagl_glsl_state_flush_version(struct yagl_glsl_state *state)
             break;
         }
     }
+
+    if (!have_precision) {
+        if (state->patch_precision) {
+            yagl_glsl_state_append_header(state, "#define highp\n");
+            yagl_glsl_state_append_header(state, "#define mediump\n");
+            yagl_glsl_state_append_header(state, "#define lowp\n");
+        }
+    }
 }
 
 static void yagl_glsl_state_move_pending(struct yagl_glsl_state *state)
@@ -843,3 +853,14 @@ clean:
 
     return result;
 }
+
+yagl_glsl_qualifier_type yagl_glsl_recognize_qualifier(const char *str)
+{
+    if (strcmp(str, "lowp") == 0 ||
+        strcmp(str, "mediump") == 0 ||
+        strcmp(str, "highp") == 0) {
+        return yagl_glsl_qualifier_precision;
+    }
+
+    return yagl_glsl_qualifier_other;
+}

diff --git a/GLESv2/yagl_glsl_state.h b/GLESv2/yagl_glsl_state.h
index 7e4a87b276cff07e8c6c52000e74a9c317f51d12..1d334da58ff195e7f39a9e94a06c4744ad0ad55b 100644 (file)
--- a/GLESv2/yagl_glsl_state.h
+++ b/GLESv2/yagl_glsl_state.h
@@ -111,6 +111,12 @@ typedef enum
     yagl_glsl_pp_op_par_close,
 } yagl_glsl_pp_expr_op;
 
+typedef enum
+{
+    yagl_glsl_qualifier_other = 0,
+    yagl_glsl_qualifier_precision,
+} yagl_glsl_qualifier_type;
+
 struct yagl_glsl_pp_token
 {
     char* macro;
@@ -160,6 +166,8 @@ struct yagl_glsl_state
 
     int have_extensions;
 
+    int have_precision;
+
     int have_samplerexternaloes;
 
     int frag_color_declared;
@@ -332,6 +340,8 @@ yagl_glsl_pp_condition_status yagl_glsl_state_pp_condition_resolve(struct yagl_g
  * @}
  */
 
+yagl_glsl_qualifier_type yagl_glsl_recognize_qualifier(const char *str);
+
 int yagl_glsl_parse(struct yagl_glsl_state *state);
 
 #endif