[Mesa-dev] [PATCH 06/24] nouveau: Add implementation of MapRenderbuffer.

[Eric Anholt]

Perhaps the easiest implementation, nouveau can directly map buffers
even if tiled, and uses separate surfaces for its texture
renderbuffers so we don't have to worry about that offset.
---
 src/mesa/drivers/dri/nouveau/nouveau_fbo.c |   46 ++++++++++++++++++++++++++++
 1 files changed, 46 insertions(+), 0 deletions(-)

diff --git a/src/mesa/drivers/dri/nouveau/nouveau_fbo.c b/src/mesa/drivers/dri/nouveau/nouveau_fbo.c
index b36b578..d56e954 100644
--- a/src/mesa/drivers/dri/nouveau/nouveau_fbo.c
+++ b/src/mesa/drivers/dri/nouveau/nouveau_fbo.c
@@ -133,6 +133,50 @@ nouveau_renderbuffer_new(struct gl_context *ctx, GLuint name)
 	return rb;
 }
 
+static void
+nouveau_renderbuffer_map(struct gl_context *ctx,
+			 struct gl_renderbuffer *rb,
+			 GLuint x, GLuint y, GLuint w, GLuint h,
+			 GLbitfield mode,
+			 GLubyte **out_map,
+			 GLint *out_stride)
+{
+	struct nouveau_surface *s = &to_nouveau_renderbuffer(rb)->surface;
+	GLubyte *map;
+	int stride;
+	int flags = 0;
+
+	if (mode & GL_MAP_READ_BIT)
+		flags |= NOUVEAU_BO_RD;
+	if (mode & GL_MAP_WRITE_BIT)
+		flags |= NOUVEAU_BO_WR;
+
+	nouveau_bo_map(s->bo, flags);
+
+	map = s->bo->map;
+	stride = s->pitch;
+
+	if (rb->Name == 0) {
+		map += stride * (rb->Height - 1);
+		stride = -stride;
+	}
+
+	map += x * s->cpp;
+	map += (int)y * stride;
+
+	*out_map = map;
+	*out_stride = stride;
+}
+
+static void
+nouveau_renderbuffer_unmap(struct gl_context *ctx,
+			   struct gl_renderbuffer *rb)
+{
+	struct nouveau_surface *s = &to_nouveau_renderbuffer(rb)->surface;
+
+	nouveau_bo_unmap(s->bo);
+}
+
 static GLboolean
 nouveau_renderbuffer_dri_storage(struct gl_context *ctx, struct gl_renderbuffer *rb,
 				 GLenum internalFormat,
@@ -268,6 +312,8 @@ nouveau_fbo_functions_init(struct dd_function_table *functions)
 #if FEATURE_EXT_framebuffer_object
 	functions->NewFramebuffer = nouveau_framebuffer_new;
 	functions->NewRenderbuffer = nouveau_renderbuffer_new;
+	functions->MapRenderbuffer = nouveau_renderbuffer_map;
+	functions->UnmapRenderbuffer = nouveau_renderbuffer_unmap;
 	functions->BindFramebuffer = nouveau_bind_framebuffer;
 	functions->FramebufferRenderbuffer = nouveau_framebuffer_renderbuffer;
 	functions->RenderTexture = nouveau_render_texture;
-- 
1.7.7