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    /* XXX unfinished */
  31 }
  32
  33 static void
  34 texture_get_values(GLcontext *ctx, struct gl_renderbuffer *rb, GLuint count,
  35                    const GLint x[], const GLint y[], void *values)
  36 {
  37    /* XXX unfinished */
  38 }
  39
  40 static void
  41 texture_put_row(GLcontext *ctx, struct gl_renderbuffer *rb, GLuint count,
  42                 GLint x, GLint y, const void *values, const GLubyte *mask)
  43 {
  44    const struct texture_renderbuffer *trb
  45       = (const struct texture_renderbuffer *) rb;
  46    const GLint z = trb->Zoffset;
  47    const GLchan *rgba = (const GLchan *) values;
  48    GLuint i;
  49    for (i = 0; i < count; i++) {
  50       if (!mask || mask[i]) {
  51          trb->Store(trb->TexImage, x + i, y, z, rgba);
  52       }
  53       rgba += 4;
  54    }
  55 }
  56
  57 static void
  58 texture_put_mono_row(GLcontext *ctx, struct gl_renderbuffer *rb, GLuint count,
  59                      GLint x, GLint y, const void *value, const GLubyte *mask)
  60 {
  61    const struct texture_renderbuffer *trb
  62       = (const struct texture_renderbuffer *) rb;
  63    const GLint z = trb->Zoffset;
  64    const GLchan *rgba = (const GLchan *) value;
  65    GLuint i;
  66    for (i = 0; i < count; i++) {
  67       if (!mask || mask[i]) {
  68          trb->Store(trb->TexImage, x + i, y, z, rgba);
  69       }
  70    }
  71 }
  72
  73 static void
  74 texture_put_values(GLcontext *ctx, struct gl_renderbuffer *rb, GLuint count,
  75                    const GLint x[], const GLint y[], const void *values,
  76                    const GLubyte *mask)
  77 {
  78    const struct texture_renderbuffer *trb
  79       = (const struct texture_renderbuffer *) rb;
  80    const GLint z = trb->Zoffset;
  81    const GLchan *rgba = (const GLchan *) values;
  82    GLuint i;
  83    for (i = 0; i < count; i++) {
  84       if (!mask || mask[i]) {
  85          trb->Store(trb->TexImage, x[i], y[i], z, rgba);
  86       }
  87       rgba += 4;
  88    }
  89 }
  90
  91 static void
  92 texture_put_mono_values(GLcontext *ctx, struct gl_renderbuffer *rb,
  93                         GLuint count, const GLint x[], const GLint y[],
  94                         const void *value, const GLubyte *mask)
  95 {
  96    const struct texture_renderbuffer *trb
  97       = (const struct texture_renderbuffer *) rb;
  98    const GLint z = trb->Zoffset;
  99    const GLchan *rgba = (const GLchan *) value;
 100    GLuint i;
 101    for (i = 0; i < count; i++) {
 102       if (!mask || mask[i]) {
 103          trb->Store(trb->TexImage, x[i], y[i], z, rgba);
 104       }
 105    }
 106 }
 107
 108
 109 static void
 110 delete_texture_wrapper(struct gl_renderbuffer *rb)
 111 {
 112    _mesa_free(rb);
 113 }
 114
 115
 116 /**
 117  * If a render buffer attachment specifies a texture image, we'll use
 118  * this function to make a gl_renderbuffer wrapper around the texture image.
 119  * This allows other parts of Mesa to access the texture image as if it
 120  * was a renderbuffer.
 121  */
 122 static void
 123 wrap_texture(GLcontext *ctx, struct gl_renderbuffer_attachment *att)
 124 {
 125    struct texture_renderbuffer *trb;
 126    const GLuint name = 0;
 127
 128    ASSERT(att->Type == GL_TEXTURE);
 129    ASSERT(att->Renderbuffer == NULL);
 130    /*
 131    ASSERT(att->Complete);
 132    */
 133
 134    trb = CALLOC_STRUCT(texture_renderbuffer);
 135    if (!trb) {
 136       _mesa_error(ctx, GL_OUT_OF_MEMORY, "wrap_texture");
 137       return;
 138    }
 139
 140    _mesa_init_renderbuffer(&trb->Base, name);
 141
 142    trb->TexImage = att->Texture->Image[att->CubeMapFace][att->TextureLevel];
 143    assert(trb->TexImage);
 144
 145    trb->Store = trb->TexImage->TexFormat->StoreTexel;
 146    assert(trb->Store);
 147
 148    trb->Zoffset = att->Zoffset;
 149
 150    trb->Base.Width = trb->TexImage->Width;
 151    trb->Base.Height = trb->TexImage->Height;
 152    trb->Base.InternalFormat = trb->TexImage->IntFormat; /* XXX fix? */
 153    trb->Base._BaseFormat = trb->TexImage->TexFormat->BaseFormat;
 154 #if 0
 155    /* fix/avoid this assertion someday */
 156    assert(trb->Base._BaseFormat == GL_RGB ||
 157           trb->Base._BaseFormat == GL_RGBA ||
 158           trb->Base._BaseFormat == GL_DEPTH_COMPONENT);
 159 #endif
 160    trb->Base.DataType = GL_UNSIGNED_BYTE;  /* XXX fix! */
 161    trb->Base.Data = trb->TexImage->Data;
 162
 163    trb->Base.GetRow = texture_get_row;
 164    trb->Base.GetValues = texture_get_values;
 165    trb->Base.PutRow = texture_put_row;
 166    trb->Base.PutMonoRow = texture_put_mono_row;
 167    trb->Base.PutValues = texture_put_values;
 168    trb->Base.PutMonoValues = texture_put_mono_values;
 169
 170    trb->Base.Delete = delete_texture_wrapper;
 171    trb->Base.AllocStorage = NULL; /* illegal! */
 172
 173    att->Renderbuffer = &(trb->Base);
 174 }
 175
 176
 177
 178 /**
 179  * Software fallback for ctx->Driver.RenderbufferTexture.
 180  * This is called via the glRenderbufferTexture1D/2D/3D() functions.
 181  * If we're unbinding a texture, texObj will be NULL.
 182  * The framebuffer of interest is ctx->DrawBuffer.
 183  * \sa _mesa_framebuffer_renderbuffer
 184  */
 185 void
 186 _mesa_renderbuffer_texture(GLcontext *ctx,
 187                            struct gl_renderbuffer_attachment *att,
 188                            struct gl_texture_object *texObj,
 189                            GLenum texTarget, GLuint level, GLuint zoffset)
 190 {
 191    if (texObj) {
 192       _mesa_set_texture_attachment(ctx, att, texObj,
 193                                    texTarget, level, zoffset);
 194
 195       wrap_texture(ctx, att);
 196    }
 197    else {
 198       _mesa_remove_attachment(ctx, att);
 199    }
 200 }