src/mesa/swrast/s_texrender.c

   1
   2 #include "main/context.h"
   3 #include "main/fbobject.h"
   4 #include "main/macros.h"
   5 #include "main/teximage.h"
   6 #include "main/renderbuffer.h"
   7 #include "swrast/swrast.h"
   8 #include "swrast/s_context.h"
   9 #include "swrast/s_texfetch.h"
  10
  11
  12 /*
  13  * Render-to-texture code for GL_EXT_framebuffer_object
  14  */
  15
  16
  17 static void
  18 delete_texture_wrapper(struct gl_context *ctx, struct gl_renderbuffer *rb)
  19 {
  20    assert(rb->RefCount == 0);
  21    free(rb);
  22 }
  23
  24 /**
  25  * Update the renderbuffer wrapper for rendering to a texture.
  26  * For example, update the width, height of the RB based on the texture size,
  27  * update the internal format info, etc.
  28  */
  29 static void
  30 update_wrapper(struct gl_context *ctx, struct gl_renderbuffer_attachment *att)
  31 {
  32    struct gl_renderbuffer *rb = att->Renderbuffer;
  33    struct swrast_renderbuffer *srb = swrast_renderbuffer(rb);
  34    struct swrast_texture_image *swImage;
  35    mesa_format format;
  36    GLuint zOffset;
  37
  38    (void) ctx;
  39
  40    swImage = swrast_texture_image(rb->TexImage);
  41    assert(swImage);
  42
  43    format = swImage->Base.TexFormat;
  44
  45    if (att->Texture->Target == GL_TEXTURE_1D_ARRAY_EXT) {
  46       zOffset = 0;
  47    }
  48    else {
  49       zOffset = att->Zoffset;
  50    }
  51
  52    /* Want to store linear values, not sRGB */
  53    rb->Format = _mesa_get_srgb_format_linear(format);
  54
  55    srb->Buffer = swImage->ImageSlices[zOffset];
  56 }
  57
  58
  59
  60 /**
  61  * Called when rendering to a texture image begins, or when changing
  62  * the dest mipmap level, cube face, etc.
  63  * This is a fallback routine for software render-to-texture.
  64  *
  65  * Called via the glRenderbufferTexture1D/2D/3D() functions
  66  * and elsewhere (such as glTexImage2D).
  67  *
  68  * The image we're rendering into is
  69  * att->Texture->Image[att->CubeMapFace][att->TextureLevel];
  70  * It'll never be NULL.
  71  *
  72  * \param fb  the framebuffer object the texture is being bound to
  73  * \param att  the fb attachment point of the texture
  74  *
  75  * \sa _mesa_FramebufferRenderbuffer_sw
  76  */
  77 void
  78 _swrast_render_texture(struct gl_context *ctx,
  79                        struct gl_framebuffer *fb,
  80                        struct gl_renderbuffer_attachment *att)
  81 {
  82    struct gl_renderbuffer *rb = att->Renderbuffer;
  83    (void) fb;
  84
  85    /* plug in our texture_renderbuffer-specific functions */
  86    rb->Delete = delete_texture_wrapper;
  87
  88    update_wrapper(ctx, att);
  89 }
  90
  91
  92 void
  93 _swrast_finish_render_texture(struct gl_context *ctx,
  94                               struct gl_renderbuffer *rb)
  95 {
  96    /* do nothing */
  97    /* The renderbuffer texture wrapper will get deleted by the
  98     * normal mechanism for deleting renderbuffers.
  99     */
 100    (void) ctx;
 101    (void) rb;
 102 }