src/mesa/swrast/s_texture.c

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 2011 VMware, Inc.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included
  14  * in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  20  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 /**
  25  * Functions for mapping/unmapping texture images.
  26  */
  27
  28
  29 #include "main/context.h"
  30 #include "main/fbobject.h"
  31 #include "main/teximage.h"
  32 #include "swrast/swrast.h"
  33 #include "swrast/s_context.h"
  34
  35
  36 /**
  37  * Allocate a new swrast_texture_image (a subclass of gl_texture_image).
  38  * Called via ctx->Driver.NewTextureImage().
  39  */
  40 struct gl_texture_image *
  41 _swrast_new_texture_image( struct gl_context *ctx )
  42 {
  43    (void) ctx;
  44    return (struct gl_texture_image *) CALLOC_STRUCT(swrast_texture_image);
  45 }
  46
  47
  48 /**
  49  * Free a swrast_texture_image (a subclass of gl_texture_image).
  50  * Called via ctx->Driver.DeleteTextureImage().
  51  */
  52 void
  53 _swrast_delete_texture_image(struct gl_context *ctx,
  54                              struct gl_texture_image *texImage)
  55 {
  56    /* Nothing special for the subclass yet */
  57    _mesa_delete_texture_image(ctx, texImage);
  58 }
  59
  60
  61 /**
  62  * Called via ctx->Driver.AllocTextureImageBuffer()
  63  */
  64 GLboolean
  65 _swrast_alloc_texture_image_buffer(struct gl_context *ctx,
  66                                    struct gl_texture_image *texImage,
  67                                    gl_format format, GLsizei width,
  68                                    GLsizei height, GLsizei depth)
  69 {
  70    struct swrast_texture_image *swImg = swrast_texture_image(texImage);
  71    GLuint bytes = _mesa_format_image_size(format, width, height, depth);
  72
  73    /* This _should_ be true (revisit if these ever fail) */
  74    assert(texImage->Width == width);
  75    assert(texImage->Height == height);
  76    assert(texImage->Depth == depth);
  77
  78    assert(!texImage->Data);
  79    texImage->Data = _mesa_align_malloc(bytes, 512);
  80
  81    if ((width == 1 || _mesa_is_pow_two(texImage->Width2)) &&
  82        (height == 1 || _mesa_is_pow_two(texImage->Height2)) &&
  83        (depth == 1 || _mesa_is_pow_two(texImage->Depth2)))
  84       swImg->_IsPowerOfTwo = GL_TRUE;
  85    else
  86       swImg->_IsPowerOfTwo = GL_FALSE;
  87
  88    return texImage->Data != NULL;
  89 }
  90
  91
  92 /**
  93  * Called via ctx->Driver.FreeTextureImageBuffer()
  94  */
  95 void
  96 _swrast_free_texture_image_buffer(struct gl_context *ctx,
  97                                   struct gl_texture_image *texImage)
  98 {
  99    if (texImage->Data && !texImage->IsClientData) {
 100       _mesa_align_free(texImage->Data);
 101    }
 102
 103    texImage->Data = NULL;
 104 }
 105
 106
 107 /**
 108  * Error checking for debugging only.
 109  */
 110 static void
 111 _mesa_check_map_teximage(struct gl_texture_image *texImage,
 112                          GLuint slice, GLuint x, GLuint y, GLuint w, GLuint h)
 113 {
 114
 115    if (texImage->TexObject->Target == GL_TEXTURE_1D)
 116       assert(y == 0 && h == 1);
 117
 118    assert(x < texImage->Width || texImage->Width == 0);
 119    assert(y < texImage->Height || texImage->Height == 0);
 120    assert(x + w <= texImage->Width);
 121    assert(y + h <= texImage->Height);
 122 }
 123
 124 /**
 125  * Map a 2D slice of a texture image into user space.
 126  * (x,y,w,h) defines a region of interest (ROI).  Reading/writing texels
 127  * outside of the ROI is undefined.
 128  *
 129  * \param texImage  the texture image
 130  * \param slice  the 3D image slice or array texture slice
 131  * \param x, y, w, h  region of interest
 132  * \param mode  bitmask of GL_MAP_READ_BIT, GL_MAP_WRITE_BIT
 133  * \param mapOut  returns start of mapping of region of interest
 134  * \param rowStrideOut  returns row stride (in bytes)
 135  */
 136 void
 137 _swrast_map_teximage(struct gl_context *ctx,
 138                      struct gl_texture_image *texImage,
 139                      GLuint slice,
 140                      GLuint x, GLuint y, GLuint w, GLuint h,
 141                      GLbitfield mode,
 142                      GLubyte **mapOut,
 143                      GLint *rowStrideOut)
 144 {
 145    GLubyte *map;
 146    GLint stride, texelSize;
 147    GLuint bw, bh;
 148
 149    _mesa_check_map_teximage(texImage, slice, x, y, w, h);
 150
 151    texelSize = _mesa_get_format_bytes(texImage->TexFormat);
 152    stride = _mesa_format_row_stride(texImage->TexFormat, texImage->Width);
 153    _mesa_get_format_block_size(texImage->TexFormat, &bw, &bh);
 154
 155    assert(texImage->Data);
 156
 157    map = texImage->Data;
 158
 159    if (texImage->TexObject->Target == GL_TEXTURE_3D ||
 160        texImage->TexObject->Target == GL_TEXTURE_2D_ARRAY) {
 161       GLuint sliceSize = _mesa_format_image_size(texImage->TexFormat,
 162                                                  texImage->Width,
 163                                                  texImage->Height,
 164                                                  1);
 165       assert(slice < texImage->Depth);
 166       map += slice * sliceSize;
 167    }
 168
 169    /* apply x/y offset to map address */
 170    map += stride * (y / bh) + texelSize * (x / bw);
 171
 172    *mapOut = map;
 173    *rowStrideOut = stride;
 174 }
 175
 176 void
 177 _swrast_unmap_teximage(struct gl_context *ctx,
 178                        struct gl_texture_image *texImage,
 179                        GLuint slice)
 180 {
 181    /* nop */
 182 }