[PATCH 3/3] glamor: Add a helper function for the common GL_QUADS fallback pattern.

[Eric Anholt]

We should do better than this with an index buffer, but for now at
least make it so that we don't have to copy the same code to new
places.

Signed-off-by: Eric Anholt <eric at anholt.net>
---
 glamor/glamor_copy.c  |  8 +-------
 glamor/glamor_rects.c |  9 +--------
 glamor/glamor_spans.c |  9 +--------
 glamor/glamor_utils.h | 17 +++++++++++++++++
 4 files changed, 20 insertions(+), 23 deletions(-)

diff --git a/glamor/glamor_copy.c b/glamor/glamor_copy.c
index 2ea270c..e2d5204 100644
--- a/glamor/glamor_copy.c
+++ b/glamor/glamor_copy.c
@@ -387,13 +387,7 @@ glamor_copy_fbo_fbo_draw(DrawablePtr src,
                       src_box->x2 - src_box->x1,
                       src_box->y2 - src_box->y1);
 
-            if (glamor_priv->gl_flavor == GLAMOR_GL_DESKTOP)
-                glDrawArrays(GL_QUADS, 0, nbox * 4);
-            else {
-                int i;
-                for (i = 0; i < nbox; i++)
-                    glDrawArrays(GL_TRIANGLE_FAN, i*4, 4);
-            }
+            glamor_glDrawArrays_GL_QUADS(glamor_priv, nbox);
         }
     }
     glDisable(GL_SCISSOR_TEST);
diff --git a/glamor/glamor_rects.c b/glamor/glamor_rects.c
index c8c92be..c378e4a 100644
--- a/glamor/glamor_rects.c
+++ b/glamor/glamor_rects.c
@@ -126,14 +126,7 @@ glamor_poly_fill_rect_gl(DrawablePtr drawable,
             if (glamor_priv->glsl_version >= 130)
                 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, nrect);
             else {
-                if (glamor_priv->gl_flavor == GLAMOR_GL_DESKTOP) {
-                    glDrawArrays(GL_QUADS, 0, nrect * 4);
-                } else {
-                    int i;
-                    for (i = 0; i < nrect; i++) {
-                        glDrawArrays(GL_TRIANGLE_FAN, i * 4, 4);
-                    }
-                }
+                glamor_glDrawArrays_GL_QUADS(glamor_priv, nrect);
             }
         }
     }
diff --git a/glamor/glamor_spans.c b/glamor/glamor_spans.c
index 7138db5..b358c60 100644
--- a/glamor/glamor_spans.c
+++ b/glamor/glamor_spans.c
@@ -134,14 +134,7 @@ glamor_fill_spans_gl(DrawablePtr drawable,
             if (glamor_priv->glsl_version >= 130)
                 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, n);
             else {
-                if (glamor_priv->gl_flavor == GLAMOR_GL_DESKTOP) {
-                    glDrawArrays(GL_QUADS, 0, 4 * n);
-                } else {
-                    int i;
-                    for (i = 0; i < n; i++) {
-                        glDrawArrays(GL_TRIANGLE_FAN, i * 4, 4);
-                    }
-                }
+                glamor_glDrawArrays_GL_QUADS(glamor_priv, nbox);
             }
         }
     }
diff --git a/glamor/glamor_utils.h b/glamor/glamor_utils.h
index 6a3bd29..0927ffb 100644
--- a/glamor/glamor_utils.h
+++ b/glamor/glamor_utils.h
@@ -1393,4 +1393,21 @@ glamor_make_current(glamor_screen_private *glamor_priv)
     }
 }
 
+/**
+ * Helper function for implementing draws with GL_QUADS on GLES2,
+ * where we don't have them.
+ */
+static inline void
+glamor_glDrawArrays_GL_QUADS(glamor_screen_private *glamor_priv, unsigned count)
+{
+    if (glamor_priv->gl_flavor == GLAMOR_GL_DESKTOP) {
+        glDrawArrays(GL_QUADS, 0, count * 4);
+    } else {
+        unsigned i;
+        for (i = 0; i < count; i++)
+            glDrawArrays(GL_TRIANGLE_FAN, i * 4, 4);
+    }
+}
+
+
 #endif
-- 
2.1.4