From: Kevin Rogovin <kevin.rogovin@intel.com>
Date: Wed, 17 Jun 2015 10:29:55 +0000 (+0300)
Subject: i965: Use _mesa_geometric_ functions appropriately
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=41b6db225f42a5d81beec1b4455ec7b504e2416d;p=mesa.git

i965: Use _mesa_geometric_ functions appropriately

Change references to gl_framebuffer::Width, Height, MaxNumLayers
and Visual::samples to use the _mesa_geometry_ convenience functions
for those places where the geometry of the gl_framebuffer is needed
(in contrast to the geometry of the intersection of the attachments
of the gl_framebuffer).

This patch is to pave the way to enable GL_ARB_framebuffer_no_attachments
on Gen7 and higher in i965.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Signed-off-by: Kevin Rogovin <kevin.rogovin@intel.com>
---

diff --git a/src/mesa/drivers/dri/i965/brw_clip_state.c b/src/mesa/drivers/dri/i965/brw_clip_state.c
index 32238341aae..dee74dba8af 100644
--- a/src/mesa/drivers/dri/i965/brw_clip_state.c
+++ b/src/mesa/drivers/dri/i965/brw_clip_state.c
@@ -32,6 +32,7 @@
 #include "brw_context.h"
 #include "brw_state.h"
 #include "brw_defines.h"
+#include "main/framebuffer.h"
 
 static void
 upload_clip_vp(struct brw_context *brw)
@@ -59,7 +60,9 @@ brw_upload_clip_unit(struct brw_context *brw)
    struct brw_clip_unit_state *clip;
 
    /* _NEW_BUFFERS */
-   struct gl_framebuffer *fb = ctx->DrawBuffer;
+   const struct gl_framebuffer *fb = ctx->DrawBuffer;
+   const float fb_width = (float)_mesa_geometric_width(fb);
+   const float fb_height = (float)_mesa_geometric_height(fb);
 
    upload_clip_vp(brw);
 
@@ -127,8 +130,8 @@ brw_upload_clip_unit(struct brw_context *brw)
    /* enable guardband clipping if we can */
    if (ctx->ViewportArray[0].X == 0 &&
        ctx->ViewportArray[0].Y == 0 &&
-       ctx->ViewportArray[0].Width == (float) fb->Width &&
-       ctx->ViewportArray[0].Height == (float) fb->Height)
+       ctx->ViewportArray[0].Width == fb_width &&
+       ctx->ViewportArray[0].Height == fb_height)
    {
       clip->clip5.guard_band_enable = 1;
       clip->clip6.clipper_viewport_state_ptr =
diff --git a/src/mesa/drivers/dri/i965/brw_misc_state.c b/src/mesa/drivers/dri/i965/brw_misc_state.c
index 67a693b5ec1..5a4515b582d 100644
--- a/src/mesa/drivers/dri/i965/brw_misc_state.c
+++ b/src/mesa/drivers/dri/i965/brw_misc_state.c
@@ -39,6 +39,7 @@
 #include "brw_state.h"
 #include "brw_defines.h"
 
+#include "main/framebuffer.h"
 #include "main/fbobject.h"
 #include "main/glformats.h"
 
@@ -46,12 +47,14 @@
 static void upload_drawing_rect(struct brw_context *brw)
 {
    struct gl_context *ctx = &brw->ctx;
+   const struct gl_framebuffer *fb = ctx->DrawBuffer;
+   const unsigned int fb_width = _mesa_geometric_width(fb);
+   const unsigned int fb_height = _mesa_geometric_height(fb);
 
    BEGIN_BATCH(4);
    OUT_BATCH(_3DSTATE_DRAWING_RECTANGLE << 16 | (4 - 2));
    OUT_BATCH(0); /* xmin, ymin */
-   OUT_BATCH(((ctx->DrawBuffer->Width - 1) & 0xffff) |
-	    ((ctx->DrawBuffer->Height - 1) << 16));
+   OUT_BATCH(((fb_width - 1) & 0xffff) | ((fb_height - 1) << 16));
    OUT_BATCH(0);
    ADVANCE_BATCH();
 }
@@ -767,7 +770,7 @@ static void upload_polygon_stipple_offset(struct brw_context *brw)
     * works just fine, and there's no window system to worry about.
     */
    if (_mesa_is_winsys_fbo(ctx->DrawBuffer))
-      OUT_BATCH((32 - (ctx->DrawBuffer->Height & 31)) & 31);
+      OUT_BATCH((32 - (_mesa_geometric_height(ctx->DrawBuffer) & 31)) & 31);
    else
       OUT_BATCH(0);
    ADVANCE_BATCH();
diff --git a/src/mesa/drivers/dri/i965/brw_sf_state.c b/src/mesa/drivers/dri/i965/brw_sf_state.c
index 014b43448ad..5d9892214a9 100644
--- a/src/mesa/drivers/dri/i965/brw_sf_state.c
+++ b/src/mesa/drivers/dri/i965/brw_sf_state.c
@@ -52,6 +52,12 @@ static void upload_sf_vp(struct brw_context *brw)
 			 sizeof(*sfv), 32, &brw->sf.vp_offset);
    memset(sfv, 0, sizeof(*sfv));
 
+   /* Accessing the fields Width and Height of gl_framebuffer to produce the
+    * values to program the viewport and scissor is fine as long as the
+    * gl_framebuffer has atleast one attachment.
+    */
+   assert(ctx->DrawBuffer->_HasAttachments);
+
    if (render_to_fbo) {
       y_scale = 1.0;
       y_bias = 0;
diff --git a/src/mesa/drivers/dri/i965/brw_state_upload.c b/src/mesa/drivers/dri/i965/brw_state_upload.c
index 84b0861aaad..08d1ac28885 100644
--- a/src/mesa/drivers/dri/i965/brw_state_upload.c
+++ b/src/mesa/drivers/dri/i965/brw_state_upload.c
@@ -41,6 +41,7 @@
 #include "brw_gs.h"
 #include "brw_wm.h"
 #include "brw_cs.h"
+#include "main/framebuffer.h"
 
 static const struct brw_tracked_state *gen4_atoms[] =
 {
@@ -660,6 +661,7 @@ brw_upload_pipeline_state(struct brw_context *brw,
    int i;
    static int dirty_count = 0;
    struct brw_state_flags state = brw->state.pipelines[pipeline];
+   unsigned int fb_samples = _mesa_geometric_samples(ctx->DrawBuffer);
 
    brw_select_pipeline(brw, pipeline);
 
@@ -696,8 +698,8 @@ brw_upload_pipeline_state(struct brw_context *brw,
       brw->ctx.NewDriverState |= BRW_NEW_META_IN_PROGRESS;
    }
 
-   if (brw->num_samples != ctx->DrawBuffer->Visual.samples) {
-      brw->num_samples = ctx->DrawBuffer->Visual.samples;
+   if (brw->num_samples != fb_samples) {
+      brw->num_samples = fb_samples;
       brw->ctx.NewDriverState |= BRW_NEW_NUM_SAMPLES;
    }
 
diff --git a/src/mesa/drivers/dri/i965/brw_wm.c b/src/mesa/drivers/dri/i965/brw_wm.c
index 45a03bba857..592a72927c3 100644
--- a/src/mesa/drivers/dri/i965/brw_wm.c
+++ b/src/mesa/drivers/dri/i965/brw_wm.c
@@ -36,6 +36,7 @@
 #include "main/formats.h"
 #include "main/fbobject.h"
 #include "main/samplerobj.h"
+#include "main/framebuffer.h"
 #include "program/prog_parameter.h"
 #include "program/program.h"
 #include "intel_mipmap_tree.h"
@@ -462,7 +463,7 @@ static void brw_wm_populate_key( struct brw_context *brw,
    GLuint lookup = 0;
    GLuint line_aa;
    bool program_uses_dfdy = fp->program.UsesDFdy;
-   bool multisample_fbo = ctx->DrawBuffer->Visual.samples > 1;
+   const bool multisample_fbo = _mesa_geometric_samples(ctx->DrawBuffer) > 1;
 
    memset(key, 0, sizeof(*key));
 
@@ -561,7 +562,7 @@ static void brw_wm_populate_key( struct brw_context *brw,
     * drawable height in order to invert the Y axis.
     */
    if (fp->program.Base.InputsRead & VARYING_BIT_POS) {
-      key->drawable_height = ctx->DrawBuffer->Height;
+      key->drawable_height = _mesa_geometric_height(ctx->DrawBuffer);
    }
 
    if ((fp->program.Base.InputsRead & VARYING_BIT_POS) || program_uses_dfdy) {
@@ -580,7 +581,7 @@ static void brw_wm_populate_key( struct brw_context *brw,
    key->persample_shading =
       _mesa_get_min_invocations_per_fragment(ctx, &fp->program, true) > 1;
    if (key->persample_shading)
-      key->persample_2x = ctx->DrawBuffer->Visual.samples == 2;
+      key->persample_2x = _mesa_geometric_samples(ctx->DrawBuffer) == 2;
 
    key->compute_pos_offset =
       _mesa_get_min_invocations_per_fragment(ctx, &fp->program, false) > 1 &&
diff --git a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
index 160dd2f6c62..72aad96bb6a 100644
--- a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
+++ b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
@@ -35,6 +35,7 @@
 #include "main/mtypes.h"
 #include "main/samplerobj.h"
 #include "program/prog_parameter.h"
+#include "main/framebuffer.h"
 
 #include "intel_mipmap_tree.h"
 #include "intel_batchbuffer.h"
@@ -738,6 +739,9 @@ brw_update_renderbuffer_surfaces(struct brw_context *brw,
                                  uint32_t *surf_offset)
 {
    GLuint i;
+   const unsigned int w = _mesa_geometric_width(fb);
+   const unsigned int h = _mesa_geometric_height(fb);
+   const unsigned int s = _mesa_geometric_samples(fb);
 
    /* Update surfaces for drawing buffers */
    if (fb->_NumColorDrawBuffers >= 1) {
@@ -748,17 +752,15 @@ brw_update_renderbuffer_surfaces(struct brw_context *brw,
             surf_offset[surf_index] = 
                brw->vtbl.update_renderbuffer_surface(
                   brw, fb->_ColorDrawBuffers[i],
-                  fb->MaxNumLayers > 0, i, surf_index);
+                  _mesa_geometric_layers(fb) > 0, i, surf_index);
 	 } else {
-            brw->vtbl.emit_null_surface_state(
-               brw, fb->Width, fb->Height, fb->Visual.samples,
+            brw->vtbl.emit_null_surface_state(brw, w, h, s,
                &surf_offset[surf_index]);
 	 }
       }
    } else {
       const uint32_t surf_index = render_target_start;
-      brw->vtbl.emit_null_surface_state(
-         brw, fb->Width, fb->Height, fb->Visual.samples,
+      brw->vtbl.emit_null_surface_state(brw, w, h, s,
          &surf_offset[surf_index]);
    }
 }
diff --git a/src/mesa/drivers/dri/i965/gen6_clip_state.c b/src/mesa/drivers/dri/i965/gen6_clip_state.c
index aaf90df2b9c..9a29366f0e0 100644
--- a/src/mesa/drivers/dri/i965/gen6_clip_state.c
+++ b/src/mesa/drivers/dri/i965/gen6_clip_state.c
@@ -31,6 +31,7 @@
 #include "brw_util.h"
 #include "intel_batchbuffer.h"
 #include "main/fbobject.h"
+#include "main/framebuffer.h"
 
 static void
 upload_clip_state(struct brw_context *brw)
@@ -145,11 +146,14 @@ upload_clip_state(struct brw_context *brw)
     * the viewport, so we can ignore this restriction.
     */
    if (brw->gen < 8) {
+      const float fb_width = (float)_mesa_geometric_width(fb);
+      const float fb_height = (float)_mesa_geometric_height(fb);
+
       for (unsigned i = 0; i < ctx->Const.MaxViewports; i++) {
          if (ctx->ViewportArray[i].X != 0 ||
              ctx->ViewportArray[i].Y != 0 ||
-             ctx->ViewportArray[i].Width != (float) fb->Width ||
-             ctx->ViewportArray[i].Height != (float) fb->Height) {
+             ctx->ViewportArray[i].Width != fb_width ||
+             ctx->ViewportArray[i].Height != fb_height) {
             dw2 &= ~GEN6_CLIP_GB_TEST;
             break;
          }
@@ -179,7 +183,7 @@ upload_clip_state(struct brw_context *brw)
 	     dw2);
    OUT_BATCH(U_FIXED(0.125, 3) << GEN6_CLIP_MIN_POINT_WIDTH_SHIFT |
              U_FIXED(255.875, 3) << GEN6_CLIP_MAX_POINT_WIDTH_SHIFT |
-             (fb->MaxNumLayers > 0 ? 0 : GEN6_CLIP_FORCE_ZERO_RTAINDEX) |
+             (_mesa_geometric_layers(fb) > 0 ? 0 : GEN6_CLIP_FORCE_ZERO_RTAINDEX) |
              ((ctx->Const.MaxViewports - 1) & GEN6_CLIP_MAX_VP_INDEX_MASK));
    ADVANCE_BATCH();
 }
diff --git a/src/mesa/drivers/dri/i965/gen6_multisample_state.c b/src/mesa/drivers/dri/i965/gen6_multisample_state.c
index ec46479ff75..36734f598fe 100644
--- a/src/mesa/drivers/dri/i965/gen6_multisample_state.c
+++ b/src/mesa/drivers/dri/i965/gen6_multisample_state.c
@@ -26,6 +26,7 @@
 #include "brw_context.h"
 #include "brw_defines.h"
 #include "brw_multisample_state.h"
+#include "main/framebuffer.h"
 
 void
 gen6_get_sample_position(struct gl_context *ctx,
@@ -34,7 +35,7 @@ gen6_get_sample_position(struct gl_context *ctx,
 {
    uint8_t bits;
 
-   switch (fb->Visual.samples) {
+   switch (_mesa_geometric_samples(fb)) {
    case 1:
       result[0] = result[1] = 0.5f;
       return;
diff --git a/src/mesa/drivers/dri/i965/gen6_scissor_state.c b/src/mesa/drivers/dri/i965/gen6_scissor_state.c
index 0111f152ef6..17b4a7fba96 100644
--- a/src/mesa/drivers/dri/i965/gen6_scissor_state.c
+++ b/src/mesa/drivers/dri/i965/gen6_scissor_state.c
@@ -39,6 +39,8 @@ gen6_upload_scissor_state(struct brw_context *brw)
    const bool render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
    struct gen6_scissor_rect *scissor;
    uint32_t scissor_state_offset;
+   const unsigned int fb_width= _mesa_geometric_width(ctx->DrawBuffer);
+   const unsigned int fb_height = _mesa_geometric_height(ctx->DrawBuffer);
 
    scissor = brw_state_batch(brw, AUB_TRACE_SCISSOR_STATE,
 			     sizeof(*scissor) * ctx->Const.MaxViewports, 32,
@@ -56,7 +58,11 @@ gen6_upload_scissor_state(struct brw_context *brw)
    for (unsigned i = 0; i < ctx->Const.MaxViewports; i++) {
       int bbox[4];
 
-      _mesa_scissor_bounding_box(ctx, ctx->DrawBuffer, i, bbox);
+      bbox[0] = 0;
+      bbox[1] = fb_width;
+      bbox[2] = 0;
+      bbox[3] = fb_height;
+      _mesa_intersect_scissor_bounding_box(ctx, i, bbox);
 
       if (bbox[0] == bbox[1] || bbox[2] == bbox[3]) {
          /* If the scissor was out of bounds and got clamped to 0 width/height
@@ -80,8 +86,8 @@ gen6_upload_scissor_state(struct brw_context *brw)
          /* memory: Y=0=top */
          scissor[i].xmin = bbox[0];
          scissor[i].xmax = bbox[1] - 1;
-         scissor[i].ymin = ctx->DrawBuffer->Height - bbox[3];
-         scissor[i].ymax = ctx->DrawBuffer->Height - bbox[2] - 1;
+         scissor[i].ymin = fb_height - bbox[3];
+         scissor[i].ymax = fb_height - bbox[2] - 1;
       }
    }
    BEGIN_BATCH(2);
diff --git a/src/mesa/drivers/dri/i965/gen6_sf_state.c b/src/mesa/drivers/dri/i965/gen6_sf_state.c
index 5809628e021..b00517ed81e 100644
--- a/src/mesa/drivers/dri/i965/gen6_sf_state.c
+++ b/src/mesa/drivers/dri/i965/gen6_sf_state.c
@@ -31,6 +31,7 @@
 #include "brw_util.h"
 #include "main/macros.h"
 #include "main/fbobject.h"
+#include "main/framebuffer.h"
 #include "intel_batchbuffer.h"
 
 /**
@@ -273,7 +274,7 @@ upload_sf_state(struct brw_context *brw)
    int i;
    /* _NEW_BUFFER */
    bool render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
-   bool multisampled_fbo = ctx->DrawBuffer->Visual.samples > 1;
+   const bool multisampled_fbo = _mesa_geometric_samples(ctx->DrawBuffer) > 1;
 
    const int urb_entry_read_offset = BRW_SF_URB_ENTRY_READ_OFFSET;
    float point_size;
diff --git a/src/mesa/drivers/dri/i965/gen6_viewport_state.c b/src/mesa/drivers/dri/i965/gen6_viewport_state.c
index 2fb0182c56e..7c8d8849f4e 100644
--- a/src/mesa/drivers/dri/i965/gen6_viewport_state.c
+++ b/src/mesa/drivers/dri/i965/gen6_viewport_state.c
@@ -30,6 +30,7 @@
 #include "brw_defines.h"
 #include "intel_batchbuffer.h"
 #include "main/fbobject.h"
+#include "main/framebuffer.h"
 #include "main/viewport.h"
 
 /* The clip VP defines the guardband region where expensive clipping is skipped
@@ -93,10 +94,10 @@ gen6_upload_sf_vp(struct brw_context *brw)
    /* _NEW_BUFFERS */
    if (render_to_fbo) {
       y_scale = 1.0;
-      y_bias = 0;
+      y_bias = 0.0;
    } else {
       y_scale = -1.0;
-      y_bias = ctx->DrawBuffer->Height;
+      y_bias = (float)_mesa_geometric_height(ctx->DrawBuffer);
    }
 
    for (unsigned i = 0; i < ctx->Const.MaxViewports; i++) {
diff --git a/src/mesa/drivers/dri/i965/gen6_wm_state.c b/src/mesa/drivers/dri/i965/gen6_wm_state.c
index 7081eb73428..d1748ba7457 100644
--- a/src/mesa/drivers/dri/i965/gen6_wm_state.c
+++ b/src/mesa/drivers/dri/i965/gen6_wm_state.c
@@ -33,6 +33,7 @@
 #include "program/program.h"
 #include "program/prog_parameter.h"
 #include "program/prog_statevars.h"
+#include "main/framebuffer.h"
 #include "intel_batchbuffer.h"
 
 static void
@@ -284,7 +285,7 @@ upload_wm_state(struct brw_context *brw)
    const struct brw_wm_prog_data *prog_data = brw->wm.prog_data;
 
    /* _NEW_BUFFERS */
-   const bool multisampled_fbo = ctx->DrawBuffer->Visual.samples > 1;
+   const bool multisampled_fbo = _mesa_geometric_samples(ctx->DrawBuffer) > 1;
 
    /* In case of non 1x per sample shading, only one of SIMD8 and SIMD16
     * should be enabled. We do 'SIMD16 only' dispatch if a SIMD16 shader
diff --git a/src/mesa/drivers/dri/i965/gen7_sf_state.c b/src/mesa/drivers/dri/i965/gen7_sf_state.c
index a20967caf5c..4fa46a8eb97 100644
--- a/src/mesa/drivers/dri/i965/gen7_sf_state.c
+++ b/src/mesa/drivers/dri/i965/gen7_sf_state.c
@@ -27,6 +27,7 @@
 #include "brw_util.h"
 #include "main/macros.h"
 #include "main/fbobject.h"
+#include "main/framebuffer.h"
 #include "intel_batchbuffer.h"
 
 static void
@@ -109,7 +110,7 @@ upload_sf_state(struct brw_context *brw)
    float point_size;
    /* _NEW_BUFFERS */
    bool render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
-   bool multisampled_fbo = ctx->DrawBuffer->Visual.samples > 1;
+   const bool multisampled_fbo = _mesa_geometric_samples(ctx->DrawBuffer) > 1;
 
    dw1 = GEN6_SF_STATISTICS_ENABLE;
 
diff --git a/src/mesa/drivers/dri/i965/gen7_viewport_state.c b/src/mesa/drivers/dri/i965/gen7_viewport_state.c
index eb596845b72..b655205ec35 100644
--- a/src/mesa/drivers/dri/i965/gen7_viewport_state.c
+++ b/src/mesa/drivers/dri/i965/gen7_viewport_state.c
@@ -26,6 +26,7 @@
 #include "brw_defines.h"
 #include "intel_batchbuffer.h"
 #include "main/fbobject.h"
+#include "main/framebuffer.h"
 #include "main/viewport.h"
 
 static void
@@ -45,10 +46,10 @@ gen7_upload_sf_clip_viewport(struct brw_context *brw)
    /* _NEW_BUFFERS */
    if (render_to_fbo) {
       y_scale = 1.0;
-      y_bias = 0;
+      y_bias = 0.0;
    } else {
       y_scale = -1.0;
-      y_bias = ctx->DrawBuffer->Height;
+      y_bias = (float)_mesa_geometric_height(ctx->DrawBuffer);
    }
 
    for (unsigned i = 0; i < ctx->Const.MaxViewports; i++) {
diff --git a/src/mesa/drivers/dri/i965/gen7_wm_state.c b/src/mesa/drivers/dri/i965/gen7_wm_state.c
index b9182758852..1c470769c7f 100644
--- a/src/mesa/drivers/dri/i965/gen7_wm_state.c
+++ b/src/mesa/drivers/dri/i965/gen7_wm_state.c
@@ -30,6 +30,7 @@
 #include "program/program.h"
 #include "program/prog_parameter.h"
 #include "program/prog_statevars.h"
+#include "main/framebuffer.h"
 #include "intel_batchbuffer.h"
 
 static void
@@ -45,7 +46,7 @@ upload_wm_state(struct brw_context *brw)
    uint32_t dw1, dw2;
 
    /* _NEW_BUFFERS */
-   bool multisampled_fbo = ctx->DrawBuffer->Visual.samples > 1;
+   const bool multisampled_fbo = _mesa_geometric_samples(ctx->DrawBuffer) > 1;
 
    dw1 = dw2 = 0;
    dw1 |= GEN7_WM_STATISTICS_ENABLE;
diff --git a/src/mesa/drivers/dri/i965/gen8_viewport_state.c b/src/mesa/drivers/dri/i965/gen8_viewport_state.c
index 322e4663b99..2d8eeb1f10f 100644
--- a/src/mesa/drivers/dri/i965/gen8_viewport_state.c
+++ b/src/mesa/drivers/dri/i965/gen8_viewport_state.c
@@ -26,6 +26,7 @@
 #include "brw_defines.h"
 #include "intel_batchbuffer.h"
 #include "main/fbobject.h"
+#include "main/framebuffer.h"
 #include "main/viewport.h"
 
 static void
@@ -33,6 +34,7 @@ gen8_upload_sf_clip_viewport(struct brw_context *brw)
 {
    struct gl_context *ctx = &brw->ctx;
    float y_scale, y_bias;
+   const float fb_height = (float)_mesa_geometric_height(ctx->DrawBuffer);
    const bool render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
 
    float *vp = brw_state_batch(brw, AUB_TRACE_SF_VP_STATE,
@@ -47,7 +49,7 @@ gen8_upload_sf_clip_viewport(struct brw_context *brw)
       y_bias = 0;
    } else {
       y_scale = -1.0;
-      y_bias = ctx->DrawBuffer->Height;
+      y_bias = fb_height;
    }
 
    for (unsigned i = 0; i < ctx->Const.MaxViewports; i++) {
@@ -116,8 +118,8 @@ gen8_upload_sf_clip_viewport(struct brw_context *brw)
       } else {
          vp[12] = ctx->ViewportArray[i].X;
          vp[13] = viewport_Xmax - 1;
-         vp[14] = ctx->DrawBuffer->Height - viewport_Ymax;
-         vp[15] = ctx->DrawBuffer->Height - ctx->ViewportArray[i].Y - 1;
+         vp[14] = fb_height - viewport_Ymax;
+         vp[15] = fb_height - ctx->ViewportArray[i].Y - 1;
       }
 
       vp += 16;