4 files changed, 84 insertions, 55 deletions
diff --git a/source/blender/gpu/intern/gpu_framebuffer.cc b/source/blender/gpu/intern/gpu_framebuffer.cc
index 600dd129aef..f4b8a4040d4 100644
--- a/source/blender/gpu/intern/gpu_framebuffer.cc
+++ b/source/blender/gpu/intern/gpu_framebuffer.cc
@@ -55,6 +55,7 @@ FrameBuffer::FrameBuffer(const char *name)
   }
   /* Force config on first use. */
   dirty_attachments_ = true;
+  dirty_state_ = true;
 
   for (int i = 0; i < ARRAY_SIZE(attachments_); i++) {
     attachments_[i].tex = NULL;
@@ -341,21 +342,30 @@ void GPU_framebuffer_config_array(GPUFrameBuffer *gpu_fb,
   }
 }
 
-/* ---------- Framebuffer Operations ----------- */
+/* ---------- Viewport & Scissor Region ----------- */
 
-#define CHECK_FRAMEBUFFER_IS_BOUND(_fb) \
-  BLI_assert(GPU_framebuffer_bound(_fb)); \
-  UNUSED_VARS_NDEBUG(_fb); \
-  ((void)0)
+/* Viewport and scissor size is stored per framebuffer.
+ * It is only reset to its original dimensions explicitely OR when binding the framebuffer after
+ * modifiying its attachments. */
+void GPU_framebuffer_viewport_set(GPUFrameBuffer *gpu_fb, int x, int y, int width, int height)
+{
+  int viewport_rect[4] = {x, y, width, height};
+  reinterpret_cast<FrameBuffer *>(gpu_fb)->viewport_set(viewport_rect);
+}
 
-/* Needs to be done after binding. */
-void GPU_framebuffer_viewport_set(GPUFrameBuffer *gpu_fb, int x, int y, int w, int h)
+void GPU_framebuffer_viewport_get(GPUFrameBuffer *gpu_fb, int r_viewport[4])
 {
-  CHECK_FRAMEBUFFER_IS_BOUND(gpu_fb);
+  reinterpret_cast<FrameBuffer *>(gpu_fb)->viewport_get(r_viewport);
+}
 
-  GPU_viewport(x, y, w, h);
+/* Reset to its attachement(s) size. */
+void GPU_framebuffer_viewport_reset(GPUFrameBuffer *gpu_fb)
+{
+  reinterpret_cast<FrameBuffer *>(gpu_fb)->viewport_reset();
 }
 
+/* ---------- Framebuffer Operations ----------- */
+
 void GPU_framebuffer_clear(GPUFrameBuffer *gpu_fb,
                            eGPUFrameBufferBits buffers,
                            const float clear_col[4],
@@ -582,19 +592,14 @@ GPUOffScreen *GPU_offscreen_create(
     return NULL;
   }
 
-  int viewport[4];
-  GPU_viewport_size_get_i(viewport);
-
   GPUFrameBuffer *fb = gpu_offscreen_fb_get(ofs);
 
   /* check validity at the very end! */
   if (!GPU_framebuffer_check_valid(fb, err_out)) {
     GPU_offscreen_free(ofs);
-    GPU_viewport(UNPACK4(viewport));
     return NULL;
   }
   GPU_framebuffer_restore();
-  GPU_viewport(UNPACK4(viewport));
   return ofs;
 }
 
diff --git a/source/blender/gpu/intern/gpu_framebuffer_private.hh b/source/blender/gpu/intern/gpu_framebuffer_private.hh
index a34fe38a267..3fba0c8de92 100644
--- a/source/blender/gpu/intern/gpu_framebuffer_private.hh
+++ b/source/blender/gpu/intern/gpu_framebuffer_private.hh
@@ -30,6 +30,7 @@
 
 #pragma once
 
+#include "BLI_math_vector.h"
 #include "BLI_span.hh"
 
 #include "MEM_guardedalloc.h"
@@ -97,6 +98,11 @@ class FrameBuffer {
   int width_, height_;
   /** Debug name. */
   char name_[DEBUG_NAME_LEN];
+  /** Framebuffer state. */
+  int viewport_[4];
+  int scissor_[4];
+  bool scissor_test_ = false;
+  bool dirty_state_;
 
  public:
   FrameBuffer(const char *name);
@@ -134,6 +140,55 @@ class FrameBuffer {
   {
     width_ = width;
     height_ = height;
+    dirty_state_ = true;
+  }
+
+  inline void viewport_set(const int viewport[4])
+  {
+    if (!equals_v4v4_int(viewport_, viewport)) {
+      copy_v4_v4_int(viewport_, viewport);
+      dirty_state_ = true;
+    }
+  }
+
+  inline void scissor_set(const int scissor[4])
+  {
+    if (!equals_v4v4_int(scissor_, scissor)) {
+      copy_v4_v4_int(scissor_, scissor);
+      dirty_state_ = true;
+    }
+  }
+
+  inline void scissor_test_set(bool test)
+  {
+    scissor_test_ = test;
+  }
+
+  inline void viewport_get(int r_viewport[4]) const
+  {
+    copy_v4_v4_int(r_viewport, viewport_);
+  }
+
+  inline void scissor_get(int r_scissor[4]) const
+  {
+    copy_v4_v4_int(r_scissor, scissor_);
+  }
+
+  inline bool scissor_test_get(void) const
+  {
+    return scissor_test_;
+  }
+
+  inline void viewport_reset(void)
+  {
+    int viewport_rect[4] = {0, 0, width_, height_};
+    viewport_set(viewport_rect);
+  }
+
+  inline void scissor_reset(void)
+  {
+    int scissor_rect[4] = {0, 0, width_, height_};
+    scissor_set(scissor_rect);
   }
 
   inline GPUTexture *depth_tex(void) const
diff --git a/source/blender/gpu/intern/gpu_state.cc b/source/blender/gpu/intern/gpu_state.cc
index fcbaa500e2d..478fd639cdd 100644
--- a/source/blender/gpu/intern/gpu_state.cc
+++ b/source/blender/gpu/intern/gpu_state.cc
@@ -191,27 +191,19 @@ void GPU_program_point_size(bool enable)
 
 void GPU_scissor_test(bool enable)
 {
-  GPUStateManager *stack = GPU_context_active_get()->state_manager;
-  auto &state = stack->mutable_state;
-  /* Set point size sign negative to disable. */
-  state.scissor_rect[2] = abs(state.scissor_rect[2]) * (enable ? 1 : -1);
+  GPU_context_active_get()->active_fb->scissor_test_set(enable);
 }
 
 void GPU_scissor(int x, int y, int width, int height)
 {
-  GPUStateManager *stack = GPU_context_active_get()->state_manager;
-  auto &state = stack->mutable_state;
-  bool enabled = state.scissor_rect[2] > 0;
-  int scissor_rect[4] = {x, y, enabled ? width : -width, height};
-  copy_v4_v4_int(state.scissor_rect, scissor_rect);
+  int scissor_rect[4] = {x, y, width, height};
+  GPU_context_active_get()->active_fb->scissor_set(scissor_rect);
 }
 
 void GPU_viewport(int x, int y, int width, int height)
 {
-  GPUStateManager *stack = GPU_context_active_get()->state_manager;
-  auto &state = stack->mutable_state;
   int viewport_rect[4] = {x, y, width, height};
-  copy_v4_v4_int(state.viewport_rect, viewport_rect);
+  GPU_context_active_get()->active_fb->viewport_set(viewport_rect);
 }
 
 void GPU_stencil_reference_set(uint reference)
@@ -267,22 +259,21 @@ eGPUStencilTest GPU_stencil_test_get()
 
 void GPU_scissor_get(int coords[4])
 {
-  GPUStateMutable &state = GPU_context_active_get()->state_manager->mutable_state;
-  copy_v4_v4_int(coords, state.scissor_rect);
+  GPU_context_active_get()->active_fb->scissor_get(coords);
 }
 
 void GPU_viewport_size_get_f(float coords[4])
 {
-  GPUStateMutable &state = GPU_context_active_get()->state_manager->mutable_state;
+  int viewport[4];
+  GPU_context_active_get()->active_fb->viewport_get(viewport);
   for (int i = 0; i < 4; i++) {
-    coords[i] = state.viewport_rect[i];
+    coords[i] = viewport[i];
   }
 }
 
 void GPU_viewport_size_get_i(int coords[4])
 {
-  GPUStateMutable &state = GPU_context_active_get()->state_manager->mutable_state;
-  copy_v4_v4_int(coords, state.viewport_rect);
+  GPU_context_active_get()->active_fb->viewport_get(coords);
 }
 
 bool GPU_depth_mask_get(void)
@@ -345,16 +336,6 @@ GPUStateManager::GPUStateManager(void)
   state.polygon_smooth = false;
   state.clip_distances = 0;
 
-  /* TODO: We should have better default for viewport and scissors.
-   * For now it's not important since they are overwritten at soon as a framebuffer is bound. */
-  mutable_state.viewport_rect[0] = 0;
-  mutable_state.viewport_rect[1] = 0;
-  mutable_state.viewport_rect[2] = 10;
-  mutable_state.viewport_rect[3] = 10;
-  mutable_state.scissor_rect[0] = 0;
-  mutable_state.scissor_rect[1] = 0;
-  mutable_state.scissor_rect[2] = -10; /* Disable */
-  mutable_state.scissor_rect[3] = 10;
   mutable_state.depth_range[0] = 0.0f;
   mutable_state.depth_range[1] = 1.0f;
   mutable_state.point_size = 1.0f;
diff --git a/source/blender/gpu/intern/gpu_state_private.hh b/source/blender/gpu/intern/gpu_state_private.hh
index a1bfefbaff5..61234c4612c 100644
--- a/source/blender/gpu/intern/gpu_state_private.hh
+++ b/source/blender/gpu/intern/gpu_state_private.hh
@@ -94,11 +94,6 @@ inline GPUState operator~(const GPUState &a)
 union GPUStateMutable {
   struct {
     /* Viewport State */
-    /** TODO put inside GPUFramebuffer. */
-    /** Offset + Extent of the drawable region inside the framebuffer. */
-    int viewport_rect[4];
-    /** Offset + Extent of the scissor region inside the framebuffer. */
-    int scissor_rect[4];
     /** TODO remove */
     float depth_range[2];
     /** TODO remove, use explicit clear calls. */
@@ -164,14 +159,7 @@ class GPUStateManager {
   GPUStateManager();
   virtual ~GPUStateManager(){};
 
-  virtual void set_state(const GPUState &state) = 0;
-  virtual void set_mutable_state(const GPUStateMutable &state) = 0;
-
-  inline void apply_state(void)
-  {
-    this->set_state(this->state);
-    this->set_mutable_state(this->mutable_state);
-  };
+  virtual void apply_state(void) = 0;
 };
 
 }  // namespace gpu