src/mesa/main/texrender.c

   1
   2 #include "context.h"
   3 #include "fbobject.h"
   4 #include "texrender.h"
   5 #include "renderbuffer.h"
   6
   7
   8 /*
   9  * Render-to-texture code for GL_EXT_framebuffer_object
  10  */
  11
  12
  13 /**
  14  * Derived from gl_renderbuffer class
  15  */
  16 struct texture_renderbuffer
  17 {
  18    struct gl_renderbuffer Base;   /* Base class object */
  19    struct gl_texture_image *TexImage;
  20    StoreTexelFunc Store;
  21    GLint Zoffset;
  22 };
  23
  24
  25
  26 static void
  27 texture_get_row(GLcontext *ctx, struct gl_renderbuffer *rb, GLuint count,
  28                 GLint x, GLint y, void *values)
  29 {
  30    const struct texture_renderbuffer *trb
  31       = (const struct texture_renderbuffer *) rb;
  32    const GLint z = trb->Zoffset;
  33    GLchan *rgbaOut = (GLchan *) values;
  34    GLuint i;
  35    for (i = 0; i < count; i++) {
  36       trb->TexImage->FetchTexelc(trb->TexImage, x + i, y, z, rgbaOut + 4 * i);
  37    }
  38 }
  39
  40 static void
  41 texture_get_values(GLcontext *ctx, struct gl_renderbuffer *rb, GLuint count,
  42                    const GLint x[], const GLint y[], void *values)
  43 {
  44    const struct texture_renderbuffer *trb
  45       = (const struct texture_renderbuffer *) rb;
  46    const GLint z = trb->Zoffset;
  47    GLchan *rgbaOut = (GLchan *) values;
  48    GLuint i;
  49    for (i = 0; i < count; i++) {
  50       trb->TexImage->FetchTexelc(trb->TexImage, x[i], y[i], z,
  51                                  rgbaOut + 4 * i);
  52    }
  53 }
  54
  55 static void
  56 texture_put_row(GLcontext *ctx, struct gl_renderbuffer *rb, GLuint count,
  57                 GLint x, GLint y, const void *values, const GLubyte *mask)
  58 {
  59    const struct texture_renderbuffer *trb
  60       = (const struct texture_renderbuffer *) rb;
  61    const GLint z = trb->Zoffset;
  62    const GLchan *rgba = (const GLchan *) values;
  63    GLuint i;
  64    for (i = 0; i < count; i++) {
  65       if (!mask || mask[i]) {
  66          trb->Store(trb->TexImage, x + i, y, z, rgba);
  67       }
  68       rgba += 4;
  69    }
  70 }
  71
  72 static void
  73 texture_put_mono_row(GLcontext *ctx, struct gl_renderbuffer *rb, GLuint count,
  74                      GLint x, GLint y, const void *value, const GLubyte *mask)
  75 {
  76    const struct texture_renderbuffer *trb
  77       = (const struct texture_renderbuffer *) rb;
  78    const GLint z = trb->Zoffset;
  79    const GLchan *rgba = (const GLchan *) value;
  80    GLuint i;
  81    for (i = 0; i < count; i++) {
  82       if (!mask || mask[i]) {
  83          trb->Store(trb->TexImage, x + i, y, z, rgba);
  84       }
  85    }
  86 }
  87
  88 static void
  89 texture_put_values(GLcontext *ctx, struct gl_renderbuffer *rb, GLuint count,
  90                    const GLint x[], const GLint y[], const void *values,
  91                    const GLubyte *mask)
  92 {
  93    const struct texture_renderbuffer *trb
  94       = (const struct texture_renderbuffer *) rb;
  95    const GLint z = trb->Zoffset;
  96    const GLchan *rgba = (const GLchan *) values;
  97    GLuint i;
  98    for (i = 0; i < count; i++) {
  99       if (!mask || mask[i]) {
 100          trb->Store(trb->TexImage, x[i], y[i], z, rgba);
 101       }
 102       rgba += 4;
 103    }
 104 }
 105
 106 static void
 107 texture_put_mono_values(GLcontext *ctx, struct gl_renderbuffer *rb,
 108                         GLuint count, const GLint x[], const GLint y[],
 109                         const void *value, const GLubyte *mask)
 110 {
 111    const struct texture_renderbuffer *trb
 112       = (const struct texture_renderbuffer *) rb;
 113    const GLint z = trb->Zoffset;
 114    const GLchan *rgba = (const GLchan *) value;
 115    GLuint i;
 116    for (i = 0; i < count; i++) {
 117       if (!mask || mask[i]) {
 118          trb->Store(trb->TexImage, x[i], y[i], z, rgba);
 119       }
 120    }
 121 }
 122
 123
 124 static void
 125 delete_texture_wrapper(struct gl_renderbuffer *rb)
 126 {
 127    ASSERT(rb->RefCount == 0);
 128    _mesa_free(rb);
 129 }
 130
 131
 132 /**
 133  * If a render buffer attachment specifies a texture image, we'll use
 134  * this function to make a gl_renderbuffer wrapper around the texture image.
 135  * This allows other parts of Mesa to access the texture image as if it
 136  * was a renderbuffer.
 137  */
 138 static void
 139 wrap_texture(GLcontext *ctx, struct gl_renderbuffer_attachment *att)
 140 {
 141    struct texture_renderbuffer *trb;
 142    const GLuint name = 0;
 143
 144    ASSERT(att->Type == GL_TEXTURE);
 145    ASSERT(att->Renderbuffer == NULL);
 146    /*
 147    ASSERT(att->Complete);
 148    */
 149
 150    trb = CALLOC_STRUCT(texture_renderbuffer);
 151    if (!trb) {
 152       _mesa_error(ctx, GL_OUT_OF_MEMORY, "wrap_texture");
 153       return;
 154    }
 155
 156    _mesa_init_renderbuffer(&trb->Base, name);
 157
 158    trb->TexImage = att->Texture->Image[att->CubeMapFace][att->TextureLevel];
 159    assert(trb->TexImage);
 160
 161    trb->Store = trb->TexImage->TexFormat->StoreTexel;
 162    assert(trb->Store);
 163
 164    trb->Zoffset = att->Zoffset;
 165
 166    trb->Base.Width = trb->TexImage->Width;
 167    trb->Base.Height = trb->TexImage->Height;
 168    trb->Base.InternalFormat = trb->TexImage->InternalFormat; /* XXX fix? */
 169    trb->Base._BaseFormat = trb->TexImage->TexFormat->BaseFormat;
 170 #if 0
 171    /* fix/avoid this assertion someday */
 172    assert(trb->Base._BaseFormat == GL_RGB ||
 173           trb->Base._BaseFormat == GL_RGBA ||
 174           trb->Base._BaseFormat == GL_DEPTH_COMPONENT);
 175 #endif
 176    trb->Base.DataType = GL_UNSIGNED_BYTE;  /* XXX fix! */
 177    trb->Base.Data = trb->TexImage->Data;
 178
 179    trb->Base.GetRow = texture_get_row;
 180    trb->Base.GetValues = texture_get_values;
 181    trb->Base.PutRow = texture_put_row;
 182    trb->Base.PutMonoRow = texture_put_mono_row;
 183    trb->Base.PutValues = texture_put_values;
 184    trb->Base.PutMonoValues = texture_put_mono_values;
 185
 186    trb->Base.Delete = delete_texture_wrapper;
 187    trb->Base.AllocStorage = NULL; /* illegal! */
 188
 189    /* XXX fix these */
 190    trb->Base.RedBits = trb->TexImage->TexFormat->RedBits;
 191    trb->Base.GreenBits = trb->TexImage->TexFormat->GreenBits;
 192    trb->Base.BlueBits = trb->TexImage->TexFormat->BlueBits;
 193    trb->Base.AlphaBits = trb->TexImage->TexFormat->AlphaBits;
 194    trb->Base.DepthBits = trb->TexImage->TexFormat->DepthBits;
 195
 196    att->Renderbuffer = &(trb->Base);
 197    trb->Base.RefCount++;
 198 }
 199
 200
 201
 202 /**
 203  * Called when rendering to a texture image begins, or when changing
 204  * the dest mipmap level, cube face, etc.
 205  * This is a fallback routine for software render-to-texture.
 206  *
 207  * Called via the glRenderbufferTexture1D/2D/3D() functions
 208  * and elsewhere (such as glTexImage2D).
 209  *
 210  * The image we're rendering into is
 211  * att->Texture->Image[att->CubeMapFace][att->TextureLevel];
 212  * It'll never be NULL.
 213  *
 214  * \param fb  the framebuffer object the texture is being bound to
 215  * \param att  the fb attachment point of the texture
 216  *
 217  * \sa _mesa_framebuffer_renderbuffer
 218  */
 219 void
 220 _mesa_render_texture(GLcontext *ctx,
 221                      struct gl_framebuffer *fb,
 222                      struct gl_renderbuffer_attachment *att)
 223 {
 224    struct gl_texture_image *newImage
 225       = att->Texture->Image[att->CubeMapFace][att->TextureLevel];
 226    struct texture_renderbuffer *trb
 227       = (struct texture_renderbuffer *) att->Renderbuffer;
 228    struct gl_texture_image *oldImage = trb ? trb->TexImage : NULL;
 229
 230    (void) fb;
 231
 232    ASSERT(newImage);
 233
 234    if (oldImage != newImage) {
 235       if (trb) {
 236          /* get rid of old wrapper */
 237          /* XXX also if Zoffset changes? */
 238          trb->Base.Delete(&trb->Base);
 239       }
 240       wrap_texture(ctx, att);
 241    }
 242 }
 243
 244
 245 void
 246 _mesa_finish_render_texture(GLcontext *ctx,
 247                             struct gl_renderbuffer_attachment *att)
 248 {
 249    /* do nothing */
 250    /* The renderbuffer texture wrapper will get deleted by the
 251     * normal mechanism for deleting renderbuffers.
 252     */
 253 }