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    _mesa_free(rb);
 128 }
 129
 130
 131 /**
 132  * If a render buffer attachment specifies a texture image, we'll use
 133  * this function to make a gl_renderbuffer wrapper around the texture image.
 134  * This allows other parts of Mesa to access the texture image as if it
 135  * was a renderbuffer.
 136  */
 137 static void
 138 wrap_texture(GLcontext *ctx, struct gl_renderbuffer_attachment *att)
 139 {
 140    struct texture_renderbuffer *trb;
 141    const GLuint name = 0;
 142
 143    ASSERT(att->Type == GL_TEXTURE);
 144    ASSERT(att->Renderbuffer == NULL);
 145    /*
 146    ASSERT(att->Complete);
 147    */
 148
 149    trb = CALLOC_STRUCT(texture_renderbuffer);
 150    if (!trb) {
 151       _mesa_error(ctx, GL_OUT_OF_MEMORY, "wrap_texture");
 152       return;
 153    }
 154
 155    _mesa_init_renderbuffer(&trb->Base, name);
 156
 157    trb->TexImage = att->Texture->Image[att->CubeMapFace][att->TextureLevel];
 158    assert(trb->TexImage);
 159
 160    trb->Store = trb->TexImage->TexFormat->StoreTexel;
 161    assert(trb->Store);
 162
 163    trb->Zoffset = att->Zoffset;
 164
 165    trb->Base.Width = trb->TexImage->Width;
 166    trb->Base.Height = trb->TexImage->Height;
 167    trb->Base.InternalFormat = trb->TexImage->InternalFormat; /* XXX fix? */
 168    trb->Base._BaseFormat = trb->TexImage->TexFormat->BaseFormat;
 169 #if 0
 170    /* fix/avoid this assertion someday */
 171    assert(trb->Base._BaseFormat == GL_RGB ||
 172           trb->Base._BaseFormat == GL_RGBA ||
 173           trb->Base._BaseFormat == GL_DEPTH_COMPONENT);
 174 #endif
 175    trb->Base.DataType = GL_UNSIGNED_BYTE;  /* XXX fix! */
 176    trb->Base.Data = trb->TexImage->Data;
 177
 178    trb->Base.GetRow = texture_get_row;
 179    trb->Base.GetValues = texture_get_values;
 180    trb->Base.PutRow = texture_put_row;
 181    trb->Base.PutMonoRow = texture_put_mono_row;
 182    trb->Base.PutValues = texture_put_values;
 183    trb->Base.PutMonoValues = texture_put_mono_values;
 184
 185    trb->Base.Delete = delete_texture_wrapper;
 186    trb->Base.AllocStorage = NULL; /* illegal! */
 187
 188    /* XXX fix these */
 189    trb->Base.RedBits = trb->TexImage->TexFormat->RedBits;
 190    trb->Base.GreenBits = trb->TexImage->TexFormat->GreenBits;
 191    trb->Base.BlueBits = trb->TexImage->TexFormat->BlueBits;
 192    trb->Base.AlphaBits = trb->TexImage->TexFormat->AlphaBits;
 193    trb->Base.DepthBits = trb->TexImage->TexFormat->DepthBits;
 194
 195    att->Renderbuffer = &(trb->Base);
 196 }
 197
 198
 199
 200 /**
 201  * Software fallback for ctx->Driver.RenderbufferTexture.
 202  * This is called via the glRenderbufferTexture1D/2D/3D() functions.
 203  * If we're unbinding a texture, texObj will be NULL.
 204  * The framebuffer of interest is ctx->DrawBuffer.
 205  * \sa _mesa_framebuffer_renderbuffer
 206  */
 207 void
 208 _mesa_renderbuffer_texture(GLcontext *ctx,
 209                            struct gl_renderbuffer_attachment *att,
 210                            struct gl_texture_object *texObj,
 211                            GLenum texTarget, GLuint level, GLuint zoffset)
 212 {
 213    if (texObj) {
 214       _mesa_set_texture_attachment(ctx, att, texObj,
 215                                    texTarget, level, zoffset);
 216
 217       wrap_texture(ctx, att);
 218    }
 219    else {
 220       _mesa_remove_attachment(ctx, att);
 221    }
 222 }